View Filing Data

^[1]

$ 4,463,336

$ 4,415,350

$ 3,759,484

3,278,145

3,098,000

2,658,046

1,185,191

1,317,350

1,101,438

225,364

193,359

147,974

959,827

1,123,991

953,464

Other income (expense)

(34,656)

(37,352)

(18,082)

Income before income taxes

38,270

(2,721)

6,790

963,441

1,083,918

942,172

298,396

398,902

331,747

Net income attributable to noncontrolling interests

665,045

685,016

610,425

19,035

6,493

Net income attributable to Westlake Chemical Corporation

$ 646,010

$ 678,523

$ 610,425

Earnings per common share attributable to Westlake Chemical Corporation (Note 9):

Basic

$ 4.88

$ 5.09

$ 4.57

Diluted

$ 4.86

$ 5.07

$ 4.55

Weighted average shares outstanding (Note 9):

Basic

131,823,707

133,111,230

133,224,256

Diluted

132,301,812

133,643,414

133,779,250

Dividends per common share (Note 9)

$ 0.6930

$ 0.5820

$ 0.4125

[1]	Revenues are attributed to countries based on location of customer.

Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 665,045	$ 685,016	$ 610,425
Pension and other post-retirement benefits liability
Pension and other post-retirement reserves adjustment (excluding amortization)	18,260	(25,766)	12,969
Settlement benefits	355	0	0
Amortization of benefits liability	2,663	924	2,712
Income tax (provision) benefit on pension and other post-retirement benefits liability	(6,443)	8,096	(6,026)
Foreign currency translation adjustments	(59,466)	(60,128)	(1,607)
Available-for-sale investments
Unrealized holding gains on investments	(4,362)	1,301	256
Reclassification of net realized loss (gains) to net income	(3,798)	(1,212)	19
Income tax (provision) benefit on available-for-sale investment	2,932	(32)	(99)
Other comprehensive (loss) income	(49,859)	(76,817)	8,224
Comprehensive income	615,186	608,199	618,649
Comprehensive income attributable to noncontrolling interests, net of tax	19,035	6,493	0
Comprehensive income attributable to Westlake Chemical Corporation	$ 596,151	$ 601,706	$ 618,649

Consolidated Statements Of Changes In Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Common Stock, Held In Treasury, At Cost [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Benefits Liability Net Of Tax [Member]	Cumulative Foreign Currency Exchange [Member]	Net Unrealized Holding Gains On Investments, Net Of Tax [Member]	Noncontrolling Interest [Member]
Number of shares, beginning balance at Dec. 31, 2012		134,374,448	568,986
Total equity, beginning balance at Dec. 31, 2012	$ 1,872,256	$ 1,344	$ (13,302)	$ 495,582	$ 1,399,472	$ (16,351)	$ 5,511	$ 0	$ 0
Net income	610,425				610,425				0
Other comprehensive (loss) income	8,224					9,655	(1,607)	176	0
Common stock repurchased, shares			683,936
Common stock repurchased	(32,918)		$ (32,918)						0
Shares issued - stock based compensation, shares		205,760
Shares issued - stock based compensation	3,437	$ 2		3,435
Stock-based compensation, net of tax on stock options exercised	12,415			12,415
Dividends paid	(55,236)				(55,236)
Number of shares, ending balance at Dec. 31, 2013		134,580,208	1,252,922
Total equity, ending balance at Dec. 31, 2013	2,418,603	$ 1,346	$ (46,220)	511,432	1,954,661	(6,696)	3,904	176	0
Net income	685,016				678,523				6,493
Other comprehensive (loss) income	(76,817)					(16,746)	(60,128)	57	0
Common stock repurchased, shares			671,791
Common stock repurchased	(52,630)		$ (52,630)						0
Shares issued - stock based compensation, shares		98,856	(137,167)
Shares issued - stock based compensation	5,524	$ 1	$ 2,478	3,045
Stock-based compensation, net of tax on stock options exercised	15,964			15,964
Dividends paid	(77,656)				(77,656)
Distributions to noncontrolling interests	(2,204)								(2,204)
Issuance of Westlake Chemical Partners LP common units	286,088								286,088
Number of shares, ending balance at Dec. 31, 2014		134,679,064	1,787,546
Total equity, ending balance at Dec. 31, 2014	3,201,888	$ 1,347	$ (96,372)	530,441	2,555,528	(23,442)	(56,224)	233	290,377
Net income	665,045				646,010				19,035
Other comprehensive (loss) income	(49,859)					14,835	(59,466)	(5,228)	0
Common stock repurchased, shares			2,701,937
Common stock repurchased	(163,138)		$ (163,138)						0
Shares issued - stock based compensation, shares		(15,820)	(44,585)
Shares issued - stock based compensation	1,063	$ 0	$ 1,198	(135)
Stock-based compensation, net of tax on stock options exercised	11,842			11,842
Dividends paid	(91,551)				(91,551)
Distributions to noncontrolling interests	(14,956)								(14,956)
Issuance of Westlake Chemical Partners LP common units	1,597								1,597
Number of shares, ending balance at Dec. 31, 2015		134,663,244	4,444,898
Total equity, ending balance at Dec. 31, 2015	$ 3,561,931	$ 1,347	$ (258,312)	$ 542,148	$ 3,109,987	$ (8,607)	$ (115,690)	$ (4,995)	$ 296,053

Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net income	$ 665,045	$ 685,016	$ 610,425
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	245,757	208,486	157,808
Provision for doubtful accounts	956	301	5,514
Amortization of debt issuance costs	2,004	1,673	1,459
Stock-based compensation expense	10,196	9,261	6,966
Loss from disposition of fixed assets	10,891	4,181	5,039
Gain from sales of equity securities	(3,798)	(1,212)	19
Gain on acquisition, net of loss on the fair value remeasurement of preexisting equity interest	(21,045)	0	0
Impairment of equity method investment	4,925	6,747	0
Deferred income taxes	39,784	58,967	93,732
Windfall tax benefits from share-based payment arrangements	(1,646)	(6,704)	(5,449)
(Income) loss from equity method investments, net of dividends	(632)	(424)	199
Other loss, net	362	1,487	372
Changes in operating assets and liabilities
Accounts receivable	62,722	33,161	(14,830)
Inventories	99,430	51,087	(46,633)
Prepaid expenses and other current assets	(4,257)	7,461	(475)
Accounts payable	(21,604)	(97,237)	13,820
Accrued liabilities	(7,640)	74,989	(15,147)
Other, net	(2,614)	(4,864)	(60,090)
Net cash provided by operating activities	1,078,836	1,032,376	752,729
Cash flows from investing activities
Acquisition of business, net of cash acquired	15,782	(611,087)	(178,309)
Additions to equity investments	0	0	(23,338)
Additions to property, plant and equipment	(491,426)	(431,104)	(679,222)
Construction of assets pending sale-leaseback	0	0	(136)
Proceeds from disposition of assets	49	181	151
Proceeds from sale of equity method investments	27,865	0	0
Proceeds from repayment of loan acquired	0	45,923	0
Proceeds from repayment of loan to affiliate	0	0	167
Proceeds from sales and maturities of securities	48,900	342,045	252,519
Purchase of securities	(605,098)	(117,332)	(367,150)
Settlements of derivative instruments	(2,248)	(1,831)	(6,920)
Net cash used for investing activities	(1,006,176)	(773,205)	(1,002,238)
Cash flows from financing activities
Capitalized debt issuance costs	0	(1,186)	0
Dividends paid	(91,551)	(77,656)	(55,236)
Distributions to noncontrolling interests	(14,856)	(2,204)	0
Net proceeds from issuance of Westlake Chemical Partners LP common units	0	286,088	0
Proceeds from exercise of stock options	1,063	5,524	3,437
Proceeds from issuance of notes payable	52,960	0	0
Repayment of notes payable	(73,615)	0	0
Repurchase of common stock for treasury	(162,459)	(52,630)	(32,918)
Windfall tax benefits from share-based payment arrangements	1,646	6,704	5,449
Net cash (used for) provided by financing activities	(286,812)	164,640	(79,268)
Effect of exchange rate changes on cash and cash equivalents	(3,924)	(4,511)	0
Net (decrease) increase in cash and cash equivalents	(218,076)	419,300	(328,777)
Cash and cash equivalents at beginning of the year	880,601	461,301	790,078
Cash and cash equivalents at end of the year	$ 662,525	$ 880,601	$ 461,301

Description Of Business And Significant Accounting Policies

12 Months Ended

Dec. 31, 2015

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Description Of Business And Significant Accounting Policies

Description of Business and Significant Accounting Policies

Description of Business

Westlake Chemical Corporation (the "Company") operates as an integrated global manufacturer and marketer of basic chemicals, vinyls, polymers and building products. These products include some of the most widely used chemicals in the world, which are fundamental to many diverse consumer and industrial markets, including flexible and rigid packaging, automotive products, coatings, residential and commercial construction as well as other durable and non-durable goods. The Company's customers range from large chemical processors and plastics fabricators to small construction contractors, municipalities and supply warehouses primarily throughout North America and Europe. The petrochemical industry is subject to price fluctuations and volatile feedstock pricing typical of a commodity-based industry, the effects of which may not be immediately passed along to customers.

Formation and Initial Public Offering of a Master Limited Partnership

In 2014, the Company formed Westlake Chemical Partners LP ("Westlake Partners") to operate, acquire and develop facilities for the processing of natural gas liquids and related assets. Also in 2014, Westlake Partners completed an initial public offering of 12,937,500 common units (the "Westlake Partners IPO"). As of December 31, 2015, Westlake Partners' assets consist of a 13.3% limited partner interest in Westlake Chemical OpCo LP ("OpCo"), as well as the general partner interest in OpCo. OpCo's assets include two natural gas liquids processing facilities at the Company's Lake Charles, Louisiana site, one natural gas liquids processing facility at the Company's Calvert City, Kentucky site and a 200-mile common carrier ethylene pipeline that runs from Mont Belvieu, Texas to the Company's Longview, Texas site. As of December 31, 2015, the Company held an 86.7% limited partner interest in OpCo and a significant interest in Westlake Partners. The operations of Westlake Partners are consolidated in the Company's financial statements.

Principles of Consolidation

The consolidated financial statements include the accounts of the Company and subsidiaries in which the Company directly or indirectly owns more than a 50% voting interest and exercises control and, when applicable, entities for which the Company has a controlling financial interest or is the primary beneficiary. Investments in majority-owned companies where the Company does not exercise control and investments in nonconsolidated affiliates (20%-50% owned companies, joint ventures and partnerships) are accounted for using the equity method of accounting. There were no undistributed earnings from equity investments included in retained earnings as of December 31, 2015.

Cash and Cash Equivalents

Cash equivalents consist of highly liquid investments that are readily convertible into cash and have a maturity of three months or less at the date of acquisition.

Investments

Investments in debt and equity securities are classified as trading, available-for-sale or held-to-maturity. Investments classified as trading are carried at estimated fair value with changes in fair value currently recognized in earnings. Investments classified as available-for-sale are carried at estimated fair value with unrealized gains and losses recorded as a component of accumulated other comprehensive income. Investments classified as held-to-maturity are carried at amortized cost. The Company periodically reviews its available-for-sale and held-to-maturity securities for other-than-temporary declines in fair value below the cost basis, and when events or changes in circumstances indicate the carrying value of an asset may not be recoverable, the investment is written down to fair value, establishing a new cost basis.

Allowance for Doubtful Accounts

The determination of the allowance for doubtful accounts is based on estimation of the amount of accounts receivable that the Company believes are unlikely to be collected. Estimating this amount requires analysis of the financial strength of the Company's customers, the use of historical experience, the Company's accounts receivable aged trial balance, and specific collectibility analysis. The allowance for doubtful accounts is reviewed quarterly. Past due balances over 90 days and high risk accounts as determined by the analysis of financial strength of customers are reviewed individually for collectibility.

Inventories

Inventories primarily include product, material and supplies. Inventories are stated at lower of cost or market. Cost is determined using the first-in, first-out ("FIFO") or average method.

Property, Plant and Equipment

Property, plant and equipment are carried at cost, net of accumulated depreciation. Cost includes expenditures for improvements and betterments that extend the useful lives of the assets and interest capitalized on significant capital projects. Capitalized interest was $10,449, $7,059 and $25,932 for the years ended December 31, 2015, 2014 and 2013, respectively. Repair and maintenance costs are charged to operations as incurred. Gains and losses on the disposition or retirement of fixed assets are reflected in the consolidated statement of operations when the assets are sold or retired.

The accounting guidance for asset retirement obligations requires the recording of liabilities equal to the fair value of asset retirement obligations and corresponding additional asset costs, when there is a legal asset retirement obligation as a result of existing or enacted law, statute or contract. The Company has conditional asset retirement obligations for the removal and disposal of hazardous materials from certain of the Company's manufacturing facilities. However, no asset retirement obligations have been recognized because the fair value of the conditional legal obligation cannot be measured due to the indeterminate settlement date of the obligation. Settlement of these conditional asset retirement obligations is not expected to have a material adverse effect on the Company's financial condition, results of operations or cash flows in any individual reporting period.

Depreciation is provided by utilizing the straight-line method over the estimated useful lives of the assets as follows:



Classification		Years

Buildings and improvements		25
Plant and equipment		25
Ethylene pipeline		35
Other		3-10

Fair Value Estimates

The Company develops estimates of fair value to allocate the purchase price paid to acquire a business to the assets acquired and liabilities assumed in an acquisition, to assess impairment of long-lived assets, goodwill and intangible assets and to record marketable securities, derivative instruments and pension plan assets. The Company uses all available information to make these fair value determinations, including the engagement of third-party consultants.

Impairment of Long-Lived Assets

The accounting guidance for the impairment or disposal of long-lived assets requires that the Company review long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Long-lived assets assessed for impairment are grouped at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future net undiscounted cash flows expected to be generated by the asset. Assets are considered to be impaired if the carrying amount of an asset exceeds the future undiscounted cash flows. The impairment recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or estimated fair value less costs to sell.

Impairment of Intangible Assets

The accounting guidance for goodwill and intangible assets requires that goodwill and indefinite-lived intangible assets are tested for impairment at least annually. Other intangible assets with finite lives are amortized over their estimated useful life and reviewed for impairment in accordance with the provisions of the accounting guidance. As of December 31, 2015, the Company's recorded goodwill was $62,016. See Note 6 for more information on the Company's annual goodwill impairment tests.

Turnaround Costs

The Company accounts for turnaround costs under the deferral method. Turnarounds are the scheduled and required shutdowns of specific operating units in order to perform planned major maintenance activities. The costs related to the significant overhaul and refurbishment activities include maintenance materials, parts and direct labor costs. The costs of the turnaround are deferred when incurred at the time of the turnaround and amortized (within depreciation and amortization) on a straight-line basis until the next planned turnaround, which ranges from three to six years. Deferred turnaround costs are presented as a component of other assets, net. The cash outflows related to these costs are included in operating activities in the consolidated statement of cash flows.

Exchanges

The Company enters into inventory exchange transactions with third parties, which involve fungible commodities. These exchanges are settled in like-kind quantities and are valued at lower of cost or market. Cost is determined using the FIFO method.

Income Taxes

The Company utilizes the liability method of accounting for deferred income taxes. Under the liability method, deferred tax assets or liabilities are recorded based upon temporary differences between the tax basis of assets and liabilities and their carrying values for financial reporting purposes. Deferred tax expense or benefit is the result of changes in the deferred tax assets and liabilities during the period. Valuation allowances are recorded against deferred tax assets when it is considered more likely than not that the deferred tax assets will not be realized.

Foreign Currency Translation

Assets and liabilities of foreign subsidiaries are translated to U.S. dollars at the exchange rate as of the end of the year. Statement of operations items are translated at the average exchange rate for the year. The resulting translation adjustment is recorded as a separate component of stockholders' equity.

Concentration of Credit Risk

Financial instruments which potentially subject the Company to concentration of risk consist principally of trade receivables from customers engaged in manufacturing polyethylene products, polyvinyl chloride ("PVC") products and PVC pipe products. The Company performs periodic credit evaluations of the customers' financial condition and generally does not require collateral. The Company maintains allowances for potential losses.

Revenue Recognition

Revenue is recognized when persuasive evidence of an arrangement exists, products are delivered to the customer, the sales price is fixed or determinable and collectability is reasonably assured. For domestic contracts, title and risk of loss passes to the customer upon delivery under executed customer purchase orders or contracts. For export contracts, the title and risk of loss passes to customers at the time specified by each contract. Provisions for discounts, rebates and returns are provided for in the same period as the related sales are recorded.

Earnings per Share

The accounting guidance for earnings per share requires the Company to present basic earnings per share and diluted earnings per share. Basic earnings per share excludes dilution and is computed by dividing income available to common stockholders by the weighted average number of shares outstanding for the period. Diluted earnings per share reflects the dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock.

Price Risk Management

The accounting guidance for derivative instruments and hedging activities requires that the Company recognize all derivative instruments on the balance sheet at fair value, and changes in the derivative's fair value must be currently recognized in earnings or comprehensive income, depending on the designation of the derivative. If the derivative is designated as a fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are recognized in earnings. If the derivative is designated as a cash flow hedge, the effective portion of the change in the fair value of the derivative is recorded in comprehensive income and is recognized in the statement of operations when the hedged item affects earnings. Ineffective portions of changes in the fair value of cash flow hedges are recognized in earnings currently.

The Company utilizes commodity price swaps to reduce price risks by entering into price swaps with counterparties and by purchasing or selling futures on established exchanges. The Company takes both fixed and variable positions, depending upon anticipated future physical purchases and sales of these commodities. The fair value of derivative financial instruments is estimated using quoted market prices in active markets and observable market-based inputs or unobservable inputs that are corroborated by market data when active markets are not available. The Company assesses both counterparty as well as its own nonperformance risk when measuring the fair value of derivative liabilities. The Company does not consider its nonperformance risk to be significant. See Note 14 for a summary of the fair value of derivative instruments.

Environmental Costs

Environmental costs relating to current operations are expensed or capitalized, as appropriate, depending on whether such costs provide future economic benefits. Remediation liabilities are recognized when the costs are considered probable and can be reasonably estimated. Measurement of liabilities is based on currently enacted laws and regulations, existing technology and undiscounted site-specific costs. Environmental liabilities in connection with properties that are sold or closed are realized upon such sale or closure, to the extent they are probable and estimable and not previously reserved. Recognition of any joint and several liabilities is based upon the Company's best estimate of its final pro rata share of the liability.

Fair Value of Financial Instruments

The amounts reported in the balance sheet for cash and cash equivalents, accounts receivable, net and accounts payable approximate their fair value due to the short maturities of these instruments. The fair value of the Company's debt at December 31, 2015 differs from the carrying value due to the Company's fixed rate senior notes. The fair value of financial instruments is estimated using quoted market prices in active markets and observable market-based inputs or unobservable inputs that are corroborated by market data when active markets are not available. See Note 14 for more information on the fair value of financial instruments.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and the disclosure of contingent assets and liabilities. Actual results could differ from those estimates.

Other

Amortization of debt issuance costs is computed on a basis which approximates the interest method over the term of the related debt. Certain other assets (see Note 6) are amortized over periods ranging from one to 30 years using the straight-line method.

Recent Accounting Pronouncements

Revenue from Contracts with Customers

In May 2014, the Financial Accounting Standards Board ("FASB") issued an accounting standards update on a comprehensive new revenue recognition standard that will supersede the existing revenue recognition guidance. The new accounting guidance creates a framework by which an entity will allocate the transaction price to separate performance obligations and recognize revenue when each performance obligation is satisfied. Under the new standard, entities will be required to use judgment and make estimates, including identifying performance obligations in a contract, estimating the amount of variable consideration to include in the transaction price, allocating the transaction price to each separate performance obligation and determining when an entity satisfies its performance obligations. The standard allows for either "full retrospective" adoption, meaning that the standard is applied to all of the periods presented with a cumulative catch-up as of the earliest period presented, or "modified retrospective" adoption, meaning the standard is applied only to the most current period presented in the financial statements with a cumulative catch-up as of the current period. In July 2015, the FASB deferred the effective date for the revenue recognition standard. The accounting standard will now be effective for reporting periods beginning after December 15, 2017. The Company is in the process of evaluating the impact that the new accounting guidance will have on its consolidated financial position, results of operations and cash flows.

Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items

In January 2015, the FASB issued an accounting standards update to simplify income statement classification by removing the concept of extraordinary items from U.S. GAAP. Under the new standard, an unusual and infrequent event or transaction is no longer allowed to be separately disclosed as "extraordinary." The standard retains the existing requirement to separately present items that are of an unusual nature or occur infrequently on a pre-tax basis within income from continuing operations. The new guidance also requires similar separate presentation of items that are both unusual and infrequent on a pre-tax basis within income from continuing operations. The standard allows for either prospective or retrospective application. If adopted prospectively, both the nature and amount of any subsequent adjustments to previously reported extraordinary items must be disclosed. The accounting standard will be effective for reporting periods beginning after December 15, 2015 and is not expected to have an impact on the Company's consolidated financial position, results of operations and cash flows.

Amendments to the Consolidation Analysis

In February 2015, the FASB issued an accounting standards update making certain changes to the current consolidation guidance. The amendments affect both the variable interest entity and voting interest entity consolidation models. The new standard changes the consideration of substantive rights, related party interests and fees paid to the decision maker when applying the variable interest entity consolidation model and eliminates certain guidance for limited partnerships and similar entities under the voting interest consolidation model. The accounting standard will be effective for annual periods beginning after December 15, 2015 and is not expected to have an impact on the Company's consolidated financial position, results of operations and cash flows.

Simplifying the Presentation of Debt Issuance Costs

In April 2015, the FASB issued an accounting standards update on simplifying the presentation of debt issuance costs, which requires all costs incurred to issue debt to be presented in the balance sheet as a direct deduction from the carrying value of the associated debt liability, consistent with the presentation of a debt discount. The accounting standard will be effective for reporting periods beginning after December 15, 2015 and is not expected to have an impact on the Company's consolidated financial position, results of operations and cash flows.

Simplifying the Measurement of Inventory

In July 2015, the FASB issued an accounting standards update that requires entities to measure inventory at the lower of cost or net realizable value rather than at the lower of cost or market. Net realizable value is the estimated selling price in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. Under the new standard, entities will no longer need to calculate other measures of "market." The new accounting guidance applies only to inventories for which cost is determined by methods other than last-in, first-out and the retail inventory method. The accounting standard will be effective for reporting periods beginning after December 15, 2016 and is not expected to have a significant impact on the Company's consolidated financial position, results of operations and cash flows.

Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements

In August 2015, the FASB issued final guidance incorporating into the Accounting Standards Codification a June 2015 SEC staff announcement that the SEC staff will not object to an entity presenting the cost of securing a revolving line of credit as an asset, regardless of whether a balance is outstanding. The announcement came in response to questions that arose after the FASB issued the Simplifying the Presentation of Debt Issuance Costs standard in April 2015, which standard requires debt issuance costs related to a recognized debt liability to be presented in the balance sheet as a direct deduction from the debt liability rather than as an asset. That standard, as issued, did not address revolving lines of credit, which may not have outstanding balances. An entity that repeatedly draws on a revolving credit facility and then repays the balance could also present the cost as an asset and reclassify all or a portion of it as a direct deduction from the liability whenever a balance is outstanding. Regardless of asset or contra-liability presentation, debt issuance costs should be amortized over the term of the arrangement. The accounting standard became effective upon announcement in June 2015 and did not have an impact on the Company's consolidated financial position, results of operations and cash flows.

Simplifying the Accounting for Measurement-Period Adjustments

In September 2015, the FASB issued an accounting standards update that requires an acquirer to recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. The guidance requires that the acquirer record, in the same period's financial statements, the effect on earnings of changes in depreciation, amortization or other income effects, if any, as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. The new guidance further requires specific disclosure pertaining to the measurement period adjustments. The accounting standard will be effective for reporting periods beginning after December 15, 2015 and is not expected to have a significant impact on the Company's consolidated financial position, results of operations and cash flows.

Balance Sheet Classification of Deferred Taxes

In November 2015, the FASB issued an accounting standards update that requires that all deferred tax assets and liabilities, along with any related valuation allowance, be classified as noncurrent on the balance sheet. As a result, each jurisdiction will now only have one net noncurrent deferred tax asset or liability. The new guidance does not change the existing requirement that only permits offsetting within a jurisdiction. The accounting standard will be effective for reporting periods beginning after December 15, 2016 and is not expected to have an impact on the Company's consolidated financial position, results of operations and cash flows. Early adoption is permitted for all entities as of the beginning of an interim or annual reporting period.

Recognition and Measurement of Financial Assets and Financial Liabilities

In January 2016, the FASB issued an accounting standards update making certain changes principally to the current guidance for equity investments, financial liabilities under the fair value option and the presentation and disclosure requirements for financial instruments. Among other things, the guidance (1) requires equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value, with changes in fair value recognized in net income; (2) provide entities with a policy election to record equity investments without readily determinable fair values at cost, less impairment, and subsequent adjustments for observable price changes (changes in the basis of these equity investments to be reported in net income); (3) requires an entity that has elected the fair value option for financial liabilities to recognize changes in fair value due to instrument-specific credit risk separately in other comprehensive income; (4) clarified current guidance related to the valuation allowance assessment when recognizing deferred tax assets resulting from unrealized losses on available-for-sale debt securities; and (5) requires specific disclosure pertaining to financial assets and financial liabilities in the financial statements. The accounting standard will be effective for reporting periods beginning after December 15, 2017. The Company is in the process of evaluating the impact that the new accounting guidance will have on its consolidated financial position, results of operations and cash flows.

Financial Instruments

12 Months Ended

Dec. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Financial Instruments

Cash Equivalents

The Company had $221,918 and $509,811 of held-to-maturity securities with original maturities of three months or less, primarily consisting of corporate debt securities, classified as cash equivalents at December 31, 2015 and 2014, respectively. The Company's investments in held-to-maturity securities are held at amortized cost, which approximates fair value.

Available-for-Sale Marketable Securities

Investments in available-for-sale securities at December 31 were classified as follows:



	2015		2014
Current	$	520,144	$	—
Non-current	48,081		15,414
Total available-for-sale securities	$	568,225	$	15,414

The cost, gross unrealized gains, gross unrealized losses and fair value of the Company's available-for-sale securities were as follows:



	December 31, 2015
	Cost		Gross Unrealized Gains		Gross Unrealized Losses ⁽¹⁾			Fair Value
Debt securities
Corporate bonds	$	336,665	$	55	$	(1,076	)	$	335,644
U.S. government debt ⁽²⁾	135,226		2		(374		)	134,854
Asset-backed securities	49,759		2		(115		)	49,646
Equity securities	54,371		466		(6,756		)	48,081
Total available-for-sale securities	$	576,021	$	525	$	(8,321	)	$	568,225



	December 31, 2014
	Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Equity securities	$	15,050	$	364	$	—	$	15,414
Total available-for-sale securities	$	15,050	$	364	$	—	$	15,414

______________________________


(1)	All unrealized loss positions were held at a loss for less than 12 months.


(2)	U.S. Treasury obligations, U.S. government agency obligations and U.S government agency mortgage-backed securities.

As of December 31, 2015 and December 31, 2014, net unrealized (losses) gains on the Company's available-for-sale securities of $(4,995) and $233, respectively, net of income tax (benefit) expense of $(2,801) and $131, respectively, were recorded in accumulated other comprehensive income. See Note 14 for the fair value hierarchy of the Company's available-for-sale securities.

As of December 31, 2015, the corporate bond securities held by the Company had maturities ranging between three months to five years; the U.S. government debt securities held by the Company, excluding U.S. government agency mortgage-backed securities, had maturities ranging between one month to three years; the U.S. government agency mortgage-backed securities held by the Company had maturities of approximately five years; and the asset-backed securities held by the Company had maturities ranging between one to six years.

The proceeds from sales and maturities of available-for-sale securities included in the consolidated statements of cash flows and the gross realized gains and losses included in the consolidated statements of operations are reflected in the table below. The cost of securities sold was determined using the specific identification method.



	Year Ended December 31,
	2015			2014			2013
Proceeds from sales and maturities of securities	$	48,900		$	342,045		$	7,770
Gross realized gains	3,830			1,311			20
Gross realized losses	(32		)	(99		)	(39		)

Accounts Receivable

12 Months Ended

Dec. 31, 2015

Accounts Receivable, Net [Abstract]

Accounts Receivable

Accounts receivable consist of the following at December 31:



	2015			2014
Trade customers	$	438,538		$	525,546
Affiliates	—			437
Allowance for doubtful accounts	(14,095		)	(13,468		)
	424,443			512,515
Federal and state taxes	60,748			8,919
Other	23,341			39,232
Accounts receivable, net	$	508,532		$	560,666

Inventories

12 Months Ended

Dec. 31, 2015

Inventory, Net [Abstract]

Inventories

Inventories consist of the following at December 31:



	2015		2014
Finished products	$	253,338	$	300,909
Feedstock, additives and chemicals	106,435		158,635
Materials and supplies	74,287		66,232
Inventories	$	434,060	$	525,776

Property, Plant And Equipment

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment, Net [Abstract]

Property, Plant And Equipment

Property, Plant and Equipment

Property, plant and equipment consist of the following at December 31:



	2015			2014
Land	$	33,051		$	21,211
Building and improvements	266,214			244,101
Plant and equipment	3,632,416			3,454,462
Other	241,829			213,707
	4,173,510			3,933,481
Less: Accumulated depreciation	(1,685,255		)	(1,531,331		)
	2,488,255			2,402,150
Construction in progress	515,812			355,407
Property, plant and equipment, net	$	3,004,067		$	2,757,557

Depreciation expense on property, plant and equipment of $209,271, $174,173 and $129,222 is included in cost of sales in the consolidated statements of operations for the years ended December 31, 2015, 2014 and 2013, respectively.

Other Assets

12 Months Ended

Dec. 31, 2015

Other Assets [Abstract]

Other Assets

Other assets consist of the following at December 31:



	2015							2014							Weighted Average Life
	Cost		Accumulated Amortization			Net		Cost		Accumulated Amortization			Net		Weighted Average Life
Intangible assets:
Licenses and intellectual property	$	79,699	$	(38,643	)	$	41,056	$	82,611	$	(35,732	)	$	46,879	15
Trademarks	39,085		(2,602		)	36,483		42,790		(759		)	42,031		20
Customer relationships	75,249		(22,572		)	52,677		75,249		(17,374		)	57,875		14
Goodwill	62,016		—			62,016		62,016		—			62,016
Other	29,320		(8,148		)	21,172		16,501		(6,871		)	9,630		7
Total intangible assets	285,369		(71,965		)	213,404		279,167		(60,736		)	218,431
Available-for-sale investments	48,081		—			48,081		15,414		—			15,414
Cost-method investments	51,334		—			51,334		57,147		—			57,147
Turnaround costs	111,078		(74,943		)	36,135		107,892		(56,493		)	51,399		5
Debt issuance costs	20,406		(13,286		)	7,120		20,406		(11,282		)	9,124		13
Other	51,682		(20,968		)	30,714		50,571		(18,245		)	32,326		3
Total deferred charges and other assets	282,581		(109,197		)	173,384		251,430		(86,020		)	165,410
Other assets, net	$	567,950	$	(181,162	)	$	386,788	$	530,597	$	(146,756	)	$	383,841

Amortization expense on other assets of $38,490, $35,986 and $30,045 is included in the consolidated statements of operations for the years ended December 31, 2015, 2014 and 2013, respectively.

Scheduled amortization of intangible assets for the next five years is as follows: $15,189, $13,219, $13,195, $11,446 and $9,950 in 2016, 2017, 2018, 2019 and 2020, respectively.

Goodwill

Goodwill is tested for impairment at least annually, or when events or changes in circumstances indicate the fair value of a reporting unit with goodwill has been reduced below its carrying value. The Company performed its annual impairment tests for the Olefins and Vinyls segments' goodwill in October 2015 and April 2015, respectively, and the impairment tests indicated that the recorded goodwill was not impaired. There has been no impairment of the Olefins or Vinyls segments' goodwill since the goodwill was initially recorded. The gross carrying amounts of goodwill for the years ended December 31, 2015 and 2014 are as follows:



	Olefins Segment		Vinyls Segment		Total
Balance at December 31, 2013	$	29,990	$	32,026	$	62,016
Goodwill acquired during the year	—		—		—
Balance at December 31, 2014	29,990		32,026		62,016
Changes in goodwill during the year	—		—		—
Balance at December 31, 2015	$	29,990	$	32,026	$	62,016

Olefins Segment Goodwill

The fair value of the Olefins segment, the reporting unit assessed, was calculated using both a discounted cash flow methodology and a market value methodology. The discounted cash flow projections were based on a nine-year forecast, from 2016 to 2024, to reflect the cyclicality of the Company's olefins business. The forecast was based on (1) prices and spreads projected by IHS Chemical, a chemical industry organization offering market and business advisory services for the chemical market, for the same period, and (2) estimates by management, including its strategic and operational plans. Other significant assumptions used in the discounted cash flow projection included sales volumes based on current capacities. The future cash flows were discounted to present value using a discount rate of 8.8%.

The significant assumptions used in determining the fair value of the reporting unit using the market value methodology include the determination of appropriate market comparables and the estimated multiples of EBITDA a willing buyer is likely to pay.

Even if the fair value of the Olefins segment decreased by 10%, the carrying value of the Olefins segment would not exceed its fair value.

Vinyls Segment Goodwill

The fair value of the pipe and foundation building products business, the reporting unit assessed, was calculated using both a discounted cash flow methodology and a market value methodology. The discounted cash flow projections were based on a nine-year forecast, from 2015 to 2023, to reflect the cyclicality of the North American housing and construction markets as the Company's pipe and foundation building products business is significantly influenced by said markets. The forecast was based on historical results and estimates by management, including its strategic and operational plans, and assumed a gradual increase in financial performance based on a housing market recovery in the United States. The future cash flows were discounted to present value using a discount rate of 11.5%.

Even if the fair value of the reporting unit decreased by 10%, the carrying value of the reporting unit would not exceed its fair value.

Accounts and Notes Payable

12 Months Ended

Dec. 31, 2015

Accounts and Notes Payable [Abstract]

Accounts and Notes Payable

Accounts and notes payable consist of the following at December 31:



	2015		2014
Accounts payable	$	229,219	$	261,062
Notes payable to banks	6,110		—
Accounts and notes payable	$	235,329	$	261,062

Long-Term Debt

12 Months Ended

Dec. 31, 2015

Long-term Debt, Unclassified [Abstract]

Long-Term Debt

Long-term debt consists of the following at December 31:



	2015		2014
3.60% senior notes due 2022	$	249,226	$	249,108
6 ½% senior notes due 2029	100,000		100,000
6 ¾% senior notes due 2032	250,000		250,000
6 ½% senior notes due 2035 (the "6 ½% GO Zone Senior Notes Due 2035")	89,000		89,000
6 ½% senior notes due 2035 (the "6 ½% IKE Zone Senior Notes Due 2035")	65,000		65,000
Loan related to tax-exempt waste disposal revenue bonds due 2027	10,889		10,889
Long-term debt, net	$	764,115	$	763,997

Revolving Credit Facility

The Company has a $400,000 senior secured revolving credit facility. The facility includes a provision permitting the Company to increase the size of the facility, up to four times, in increments of at least $25,000 each (up to a maximum of $200,000) under certain circumstances if the lenders agree to commit to such an increase.

The facility allows the Company to borrow up to (1) 85% of the net amount of eligible accounts receivable, plus (2) the lesser of (a) 70% of the value of the lower of cost or market of eligible inventory, or (b) 85% of the appraised net orderly liquidation value of all eligible inventory, plus (3) 100% of cash held in an account with the agent under the credit facility and subject to a control agreement with the agent, minus (4) such reserves as the agent may establish. The facility includes a $400,000 sub-limit for letters of credit, and any outstanding letters of credit will be deducted from availability under the facility.

At December 31, 2015, the Company had no borrowings outstanding under the revolving credit facility. Any borrowings under the facility will bear interest at either LIBOR plus a spread ranging from 1.25% to 1.75%, provided that so long as the Company is rated investment grade, the margin for LIBOR loans will not exceed 1.50%, or a base rate plus a spread ranging from 0.0% to 0.50%. The revolving credit facility also requires an unused commitment fee of 0.25% per annum. All interest rates under the facility are subject to monthly grid pricing adjustments based on prior month average daily loan availability. The revolving credit facility matures on July 17, 2019. As of December 31, 2015, the Company had outstanding letters of credit totaling $30,098 and borrowing availability of $320,843 under the revolving credit facility.

The Company's revolving credit facility generally restricts the Company's ability to make distributions unless, on a pro forma basis after giving effect to the distribution, the borrowing availability under the facility equals or exceeds the greater of (1) 20% of the commitments under the facility and (2) $80,000; or the borrowing availability under the facility equals or exceeds the greater of (1) 15% of the commitments under the facility and (2) $60,000, and the Company's fixed charge coverage ratio is at least 1.0:1. However, the Company may make specified distributions up to an aggregate of $82,700 in 2016, to be increased by 5% in each fiscal year thereafter, on an aggregate basis, for each fiscal year.

In order to make acquisitions or investments, the Company's revolving credit facility provides that (1) the Company must maintain a minimum borrowing availability of at least the greater of $60,000 or 15% of the total bank commitments under its revolving credit facility or (2) the Company must maintain a minimum borrowing availability of at least the greater of $50,000 or 12.5% of the total bank commitments under the Company's revolving credit facility and meet a minimum fixed charge coverage ratio of 1.0:1 under its revolving credit facility. Notwithstanding the foregoing, the Company may make investments in the aggregate up to the greater of $50,000 and 1.25% of tangible assets and acquisitions in the aggregate up to the greater of $100,000 and 2.5% of tangible assets, if, on a pro forma basis after giving effect to the acquisition or investment, either (X) the borrowing availability under the facility equals or exceeds the greater of (A) 12.5% of the total bank commitments under the facility and (B) $50,000, but is less than the greater of (A) 15% of the total bank commitments and (B) $60,000, or (Y) the Company's fixed charge coverage ratio is at least 1.0:1.

The revolving credit facility contains other customary covenants and events of default that impose significant operating and financial restrictions on the Company. These restrictions, among other things, provide limitations on the occurrence of additional indebtedness and the Company's ability to create liens, to engage in certain affiliate transactions and to engage in sale-leaseback transactions.

3.60% Senior Notes due 2022

In July 2012, the Company issued $250,000 aggregate principal amount of its 3.60% senior notes due 2022 (the "3.60% Notes Due 2022"). The 3.60% Notes Due 2022 are unsecured and were issued with an original issue discount of $1,183. There is no sinking fund and no scheduled amortization of the 3.60% Notes Due 2022 prior to maturity. The Company may optionally redeem the 3.60% Notes Due 2022 at any time and from time to time prior to April 15, 2022 (three months prior to the maturity date) for 100% of the principal plus accrued interest and a discounted "make whole" payment. On or after April 15, 2022, the Company may optionally redeem the 3.60% Notes Due 2022 for 100% of the principal plus accrued interest. The holders of the 3.60% Notes Due 2022 may require the Company to repurchase the 3.60% Notes Due 2022 at a price of 101% of their principal amount, plus accrued and unpaid interest to the date of repurchase, upon the occurrence of both a "change of control" and, within 60 days of such change of control, a "below investment grade rating event" (as such terms are defined in the indenture governing the 3.60% Notes Due 2022). All domestic subsidiaries of the Company that guarantee other indebtedness of the Company or of another guarantor of the 3.60% Notes Due 2022 in excess of $5,000 are guarantors of the 3.60% Notes Due 2022.

The indenture governing the 3.60% Notes Due 2022 contains customary events of default and covenants that will restrict the Company's and certain of its subsidiaries' ability to (1) incur certain secured indebtedness, (2) engage in certain sale-leaseback transactions and (3) consolidate, merge or transfer all or substantially all of the Company's assets.

GO Zone Bonds

In December 2010, the Louisiana Local Government Environmental Facility and Development Authority (the "Authority"), a political subdivision of the State of Louisiana, completed the offering of $89,000 of 6 ½% tax-exempt revenue bonds due November 1, 2035 under the Gulf Opportunity Zone Act of 2005 (the "GO Zone Act"). The bonds are subject to optional redemption by the Authority upon the direction of the Company at any time prior to November 1, 2020 for 100% of the principal plus accrued interest and a discounted "make whole" payment. On or after November 1, 2020, the bonds are subject to optional redemption by the Authority upon the direction of the Company for 100% of the principal plus accrued interest.

In July 2010, the Authority completed the reoffering of $100,000 of 6 ½% tax-exempt revenue bonds due August 1, 2029 under the GO Zone Act. The bonds are subject to optional redemption by the Authority upon the direction of the Company at any time prior to August 1, 2020 for 100% of the principal plus accrued interest and a discounted "make whole" payment. On or after August 1, 2020, the bonds are subject to optional redemption by the Authority upon the direction of the Company for 100% of the principal plus accrued interest.

In December 2007, the Authority issued $250,000 of 6 ¾% tax-exempt revenue bonds due November 1, 2032 under the GO Zone Act. The bonds are subject to optional redemption by the Authority upon the direction of the Company at any time prior to November 1, 2017 for 100% of the principal plus accrued interest and a discounted "make whole" payment. On or after November 1, 2017, the bonds are subject to optional redemption by the Authority upon the direction of the Company for 100% of the principal plus accrued interest.

Each series of the bonds is subject to redemption and the holders may require the bonds to be repurchased upon a change of control or a change in or loss of the current tax status of the bonds. In addition, the bonds are subject to optional redemption by the Authority upon the direction of the Company if certain events have occurred in connection with the operation of the projects for which the bond proceeds may be used, including if the Company has determined that the continued operation of any material portion of the projects would be impracticable, uneconomical or undesirable for any reason.

In connection with each offering of the bonds, the Company entered into a loan agreement with the Authority pursuant to which the Company agreed to pay all of the principal, premium, if any, and interest on the bonds and certain other amounts to the Authority. The net proceeds from the offerings were loaned by the Authority to the Company. The Company used the proceeds to expand, refurbish and maintain certain of its facilities in the Louisiana Parishes of Calcasieu and Ascension. The bonds are unsecured and rank equally in right of payment with other existing and future unsecured senior indebtedness. All domestic restricted subsidiaries that guarantee other debt of the Company or of another guarantor of the 6 ½% senior notes due 2029, the 6 ¾% senior notes due 2032 and the 6 ½% GO Zone Senior Notes Due 2035 (collectively, and including the 6 ½% IKE Zone Senior Notes Due 2035, the "Senior Notes") in excess of $5,000 are guarantors of the bonds. As of December 31, 2015, the Company had drawn all the proceeds from the 6 ½% bonds due 2029, 6 ¾% bonds due 2032 and 6 ½% bonds due 2035.

IKE Zone Bonds

In December 2010, the Authority completed the offering of $65,000 of 6 ½% tax-exempt revenue bonds due November 1, 2035 under Section 704 of the Emergency Economic Stabilization Act of 2008. The bonds are subject to optional redemption by the Authority upon the direction of the Company at any time prior to November 1, 2020 for 100% of the principal plus accrued interest and a discounted "make whole" payment. On or after November 1, 2020, the bonds are subject to optional redemption by the Authority upon the direction of the Company for 100% of the principal plus accrued interest. The bonds are subject to redemption, repurchase by the holders upon a change of control or a change in or loss of the current tax status of the bonds and optional redemption by the Authority under terms substantially similar to the terms for the GO Zone Bonds.

In connection with the offering of the bonds, the Company entered into a loan agreement with the Authority pursuant to which the Company agreed to pay all of the principal, premium, if any, and interest on the bonds and certain other amounts to the Authority. The net proceeds from the offering were loaned by the Authority to the Company. The Company used the proceeds to expand, refurbish and maintain certain of its facilities in the Louisiana Parish of Calcasieu. The 6 ½% IKE Zone Senior Notes Due 2035 are unsecured and rank equally in right of payment with other existing and future unsecured senior indebtedness. All domestic restricted subsidiaries that guarantee other debt of the Company or of another guarantor of the Senior Notes in excess of $5,000 are guarantors of the 6 ½% IKE Zone Senior Notes Due 2035. As of December 31, 2015, the Company had drawn all the proceeds from the 6 ½% IKE Zone Senior Notes Due 2035.

The indentures governing the Senior Notes contain customary covenants and events of default. Accordingly, these agreements generally impose significant operating and financial restrictions on the Company. These restrictions, among other things, provide limitations on incurrence of additional indebtedness, the payment of dividends, certain investments and acquisitions and sales of assets. However, the effectiveness of certain of these restrictions is currently suspended because the Senior Notes are currently rated investment grade by at least two nationally recognized credit rating agencies. The most significant of these provisions, if it were currently effective, would restrict the Company from incurring additional debt, except specified permitted debt (including borrowings under its credit facility), when the Company's fixed charge coverage ratio is below 2.0:1. These limitations are subject to a number of important qualifications and exceptions, including, without limitation, an exception for the payment of the Company's regular quarterly dividend of up to $0.10 per share. If the restrictions were currently effective, distributions in excess of $100,000 would not be allowed unless, after giving pro forma effect to the distribution, the Company's fixed charge coverage ratio is at least 2.0:1 and such payment, together with the aggregate amount of all other distributions after January 13, 2006, is less than the sum of 50% of the Company's consolidated net income for the period from October 1, 2003 to the end of the most recent quarter for which financial statements have been filed, plus 100% of net cash proceeds received after October 1, 2003 as a contribution to the Company's common equity capital or from the issuance or sale of certain securities, plus several other adjustments.

Revenue Bonds

In December 1997, the Company entered into a loan agreement with a public trust established for public purposes for the benefit of the Parish of Calcasieu, Louisiana. The public trust issued $10,889 principal amount of tax-exempt waste disposal revenue bonds in order to finance the Company's construction of waste disposal facilities for an ethylene plant. The waste disposal revenue bonds expire in December 2027 and are subject to redemption and mandatory tender for purchase prior to maturity under certain conditions. Interest on the waste disposal revenue bonds accrues at a rate determined by a remarketing agent and is payable quarterly. The interest rate on the waste disposal revenue bonds at December 31, 2015 and 2014 was 0.07% and 0.05%, respectively.

As of December 31, 2015, the Company was in compliance with all of the covenants with respect to the 3.60% Notes Due 2022, the Senior Notes, the waste disposal revenue bonds and its revolving credit facility.

The weighted average interest rate on all long-term debt was 5.5% at December 31, 2015 and 2014.

As of December 31, 2015, the Company had no maturities of long-term debt until 2022.

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity The Company's Board of Directors has declared regular quarterly dividends to holders of its common stock aggregating $91,551, $77,656 and $55,236 for the years ended December 31, 2015, 2014 and 2013, respectively. Common Stock Each share of common stock entitles the holder to one vote on all matters on which holders are permitted to vote, including the election of directors. There are no cumulative voting rights. Accordingly, holders of a majority of the total votes entitled to vote in an election of directors will be able to elect all of the directors standing for election. Subject to preferences that may be applicable to any outstanding preferred stock, the holders of the common stock will share equally on a per share basis any dividends when, as and if declared by the Board of Directors out of funds legally available for that purpose. If the Company is liquidated, dissolved or wound up, the holders of the Company's common stock will be entitled to a ratable share of any distribution to stockholders, after satisfaction of all the Company's liabilities and of the prior rights of any outstanding class of the Company's preferred stock. The Company's common stock has no preemptive or conversion rights or other subscription rights. There are no redemption or sinking fund provisions applicable to the Company's common stock. On February 14, 2014, the Company's Board of Directors authorized a two-for-one split of the Company's common stock. Stockholders of record as of February 28, 2014 were entitled to one additional share for every share outstanding, which was distributed on March 18, 2014. The total number of authorized common stock shares and associated par value were unchanged by this stock split. All share amounts and per share data included in the accompanying consolidated financial statements and related notes for the year ended December 31, 2013 has been restated to reflect the effect of the stock split. In 2014, the stockholders of the Company approved an amendment to the Company's Amended and Restated Certificate of Incorporation to increase the Company's authorized shares of common stock from 150,000,000 shares to 300,000,000 shares, par value $0.01 per share. The Company issued 134,663,244 and 134,679,064 shares of common stock as of December 31, 2015 and 2014, respectively. Preferred Stock The Company's charter authorizes the issuance of shares of preferred stock. The Company's Board of Directors has the authority, without shareholder approval, to issue preferred shares from time to time in one or more series, and to fix the number of shares and terms of each such series. The Board may determine the designations and other terms of each series including dividend rates, whether dividends will be cumulative or non-cumulative, redemption rights, liquidation rights, sinking fund provisions, conversion or exchange rights and voting rights. Stock Repurchase Program In August 2011, the Company's Board of Directors authorized a stock repurchase program of the Company's common stock totaling $100,000 (the "2011 Program"). As of March 31, 2015, the Company had repurchased 1,944,161 shares of its common stock for an aggregate purchase price of approximately $100,000 under the 2011 Program, the full amount of the 2011 Program. In November 2014, the Company's Board of Directors approved a new $250,000 share repurchase program (the "2014 Program"). On November 20, 2015, the Company's Board of Directors approved the expansion of the 2014 Program by an additional $150,000. The total number of shares repurchased by the Company under the 2014 Program was 2,682,489 for the year ended December 31, 2015. Any shares repurchased under the 2011 and 2014 Programs are held by the Company as treasury stock and may be used for general corporate purposes, including for the 2013 Omnibus Incentive Plan. Beginning in 2014, the Company began delivering treasury shares to employees and nonemployee directors for options exercised and for the settlement of restricted stock units. The cost of treasury shares delivered was determined using the specific identification method.

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(d),(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 4.E)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29-31)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section C

Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income

12 Months Ended

Dec. 31, 2015

Accumulated Other Comprehensive Income

Accumulated Other Comprehensive Loss

Changes in accumulated other comprehensive income (loss) by component were as follows:



	Benefits Liability, Net of Tax			Cumulative Foreign Currency Exchange			Net Unrealized Holding Gains on Investments, Net of Tax			Total
Balances at December 31, 2013	$	(6,696	)	$	3,904		$	176		$	(2,616	)
Other comprehensive (loss) income before reclassifications	(17,314		)	(60,128		)	834			(76,608		)
Amounts reclassified from accumulated other comprehensive loss	568			—			(777		)	(209		)
Net other comprehensive (loss) income for the year	(16,746		)	(60,128		)	57			(76,817		)
Balances at December 31, 2014	(23,442		)	(56,224		)	233			(79,433		)
Other comprehensive income (loss) before reclassifications	12,877			(59,466		)	(2,795		)	(49,384		)
Amounts reclassified from accumulated other comprehensive loss	1,958			—			(2,433		)	(475		)
Net other comprehensive income (loss) for the year	14,835			(59,466		)	(5,228		)	(49,859		)
Balances at December 31, 2015	$	(8,607	)	$	(115,690	)	$	(4,995	)	$	(129,292	)

The following table provides the details of the amounts reclassified from accumulated other comprehensive income (loss) into net income in the consolidated statements of operations:



Details about Accumulated Other Comprehensive Income (Loss) Components	Location of Reclassification (Income (Expense)) in Consolidated Statements of Operations	Year Ended December 31,
		2015			2014			2013
Amortization of pension and other post-retirement items
Prior service costs	(1)	$	—		$	(347	)	$	(381	)
Net loss	(1)	(2,663		)	(577		)	(2,331		)
Settlement benefits	(1)	(355		)	—			—
		(3,018		)	(924		)	(2,712		)
	Provision for income taxes	1,060			356			1,043
		(1,958		)	(568		)	(1,669		)
Net unrealized gains on available-for- sale investments
Realized gain (loss) on available- for-sale investments	Other income (expense), net	3,798			1,212			(19		)
	Provision for income taxes	(1,365		)	(435		)	7
		2,433			777			(12		)
Total reclassifications for the period		$	475		$	209		$	(1,681	)

______________________________


(1)	These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost. For additional information, see Note 11.

The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e689-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669619-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e716-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e709-108580

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Reclassification Adjustments
-URI http://asc.fasb.org/extlink&oid=6522872

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Employee Benefits

12 Months Ended

Dec. 31, 2015

Employee Benefits

Defined Contribution Plans

U.S. Plans

The Company has a defined contribution savings plan covering all U.S. regular full-time and part-time employees whereby eligible employees may elect to contribute up to 100% of their annual compensation, subject to an annual plan limit in line with the annual elective contribution limit as determined by the Internal Revenue Service. The Company matches 100% of an employee's contribution up to the first 4% of such employee's compensation. The Company may, at its discretion, make an additional non-matching contribution in an amount as the Board of Directors may determine. For the years ended December 31, 2015, 2014 and 2013, the Company charged approximately $7,594, $6,856 and $6,022, respectively, to expense for these contributions.

Further, within the defined contribution savings plan, the Company also makes an annual retirement contribution to substantially all employees of one subsidiary who have completed one year of service. The Company's contributions to the plan are determined as a percentage of employees' base and overtime pay. For the years ended December 31, 2015, 2014 and 2013, the Company charged approximately $11,715, $8,309 and $6,227, respectively, to expense for these contributions.

Non-U.S. Plans

The Company has various defined contribution plans in Germany, the United Kingdom, Italy and Belgium covering eligible employees of our European operations. The Company's contributions to the plans are based on applicable laws in each country. Contributions to the Company's non-U.S. defined contribution plans are made by both the employee and the Company. For the years ended December 31, 2015 and 2014, the Company charged approximately $1,912 and $416, respectively, to expense for its contributions to these plans.

Defined Benefit Plans

U.S. Plans

The Company has noncontributory defined benefit pension plans that cover certain eligible salaried and wage employees of one subsidiary. However, eligibility for both plans has been frozen. Benefits for salaried employees under these plans are based primarily on years of service and employees' pay near retirement. Benefits for wage employees are based upon years of service and a fixed amount as periodically adjusted. The Company recognizes the years of service prior to the Company's acquisition of the subsidiary's facilities for purposes of determining vesting, eligibility and benefit levels for certain employees of the subsidiary and for determining vesting and eligibility for certain other employees of the subsidiary. The measurement date for these plans is December 31.

In December 2014, the Company announced a plan amendment to one of the Company's defined benefit pension plans. Under the plan amendment, no additional benefits may be earned by participants after January 31, 2015 and participants' accrued benefit will freeze at the level earned as of January 31, 2015. In addition, the amendment added a lump sum payment option effective February 1, 2015. The Company made a similar plan amendment to its other defined benefit pension plan in 2012. In conjunction with both of the defined benefit pension plans' amendments, the Company amended, in 2014 and 2012, its defined contribution savings plan to allow participants impacted by the amendments to participate in the Company's annual retirement contribution program.

Non-U.S. Plans

The Company has defined benefit pension plans covering current and former employees associated with our European operations. These pension plans are closed to new participants and are for employees in Germany who commenced employment before July 1, 2007. Benefits for employees for these plans are based primarily on employees' pay near retirement. The non-U.S. plans are unfunded as no contributions have been made to the plans and therefore, have no plan assets. The measurement date for these plans is December 31.

Details of the changes in benefit obligations, plan assets and funded status of the Company's pension plans are as follows:



	2015						2014
	U.S. Plans			Non-U.S. Plans			U.S. Plans			Non-U.S. Plans
Change in benefit obligation
Benefit obligation, beginning of year	$	67,010		$	122,701		$	57,946		$	—
Benefit obligation assumed with acquisition	—			—			—			117,970
Service cost	29			1,661			334			602
Interest cost	2,015			2,110			2,322			1,366
Actuarial (gain) loss	(2,330		)	(17,310		)	9,165			15,425
Benefits paid	(4,532		)	(2,139		)	(2,757		)	(898		)
Foreign exchange effects	—			(12,202		)	—			(11,764		)
Benefit obligation, end of year	$	62,192		$	94,821		$	67,010		$	122,701

Change in plan assets
Fair value of plan assets, beginning of year	$	53,415		$	—		$	49,236		$	—
Actual return	(268		)	—			2,953			—
Employer contribution	2,148			2,139			3,983			898
Benefits paid	(4,532		)	(2,139		)	(2,757		)	(898		)
Fair value of plan assets, end of year	$	50,763		$	—		$	53,415		$	—
Funded status, end of year	$	(11,429	)	$	(94,821	)	$	(13,595	)	$	(122,701	)



	2015						2014
	U.S. Plans			Non-U.S. Plans			U.S. Plans			Non-U.S. Plans
Amounts recognized in the consolidated balance sheet at December 31
Noncurrent liabilities	$	(11,429	)	$	(94,821	)	$	(13,595	)	$	(122,701	)
Net amount recognized	$	(11,429	)	$	(94,821	)	$	(13,595	)	$	(122,701	)



	2015					2014
	U.S. Plans		Non-U.S. Plans			U.S. Plans		Non-U.S. Plans
Amounts recognized in accumulated other comprehensive income
Net loss (gain)	$	14,755	$	(4,919	)	$	15,482	$	15,425
Foreign exchange effects	—		1,986			—		—
Total before tax ⁽¹⁾	$	14,755	$	(2,933	)	$	15,482	$	15,425

______________________________


(1)	After-tax totals for pension benefits were $6,812 and $20,315 for 2015 and 2014, respectively, and are reflected in stockholders' equity as accumulated other comprehensive loss.

In the United States, the Pension Protection Act of 2006 (the "Pension Protection Act") established a relationship between a qualified pension plan's funded status and the actual benefits that can be provided. Restrictions on plan benefits and additional funding and notice requirements are imposed when a plan's funded status is less than certain threshold levels. For the 2015 plan year, the funded status for the Company's U.S. pension plans are above 80%, with both plans' funded status above 100%. Accordingly, the Company's U.S. pension plans are exempt from the Pension Protection Act's benefit restrictions.

Pension plans with an accumulated benefit obligation in excess of plan assets at December 31 are as follows:



	2015						2014
Information for pension plans with an accumulated benefit obligation in excess of plan assets	U.S. Plans			Non-U.S. Plans			U.S. Plans			Non-U.S. Plans
Projected benefit obligation	$	(62,192	)	$	(94,821	)	$	(67,010	)	$	(122,701	)
Accumulated benefit obligation	(62,192		)	(93,231		)	(67,010		)	(119,258		)
Fair value of plan assets	50,763			—			53,415			—

The following table provides the components of net periodic benefit costs, other changes in plan assets and benefit obligation recognized in other comprehensive income.



	Year Ended December 31,
	2015						2014					2013
	U.S. Plans			Non-U.S. Plans			U.S. Plans			Non-U.S. Plans		U.S. Plans
Components of net periodic benefit cost
Service cost	$	29		$	1,661		$	334		$	602	$	1,091
Interest cost	2,015			2,110			2,322			1,366		2,047
Expected return on plan assets	(2,960		)	—			(3,140		)	—		(2,854		)
Net amortization	1,270			1,048			571			—		2,255
Settlement benefits	355			—			—			—		—
Net periodic benefit cost	$	709		$	4,819		$	87		$	1,968	$	2,539

Other changes in plan assets and benefit obligation recognized in other comprehensive income (OCI)
Net loss (gain) emerging	$	898		$	(17,310	)	$	9,352		$	15,425	$	(12,468	)
Amortization of net loss	(1,270		)	(1,048		)	(274		)	—		(1,958		)
Amortization of prior service cost	—			—			(297		)	—		(297		)
Settlement benefits	(355		)	—			—			—		—
Total recognized in OCI	$	(727	)	$	(18,358	)	$	8,781		$	15,425	$	(14,723	)
Total net periodic benefit cost and OCI	$	(18	)	$	(13,539	)	$	8,868		$	17,393	$	(12,184	)

The estimated prior service cost and net loss for the defined benefit plans that will be amortized from accumulated other comprehensive income into net periodic benefit cost during 2016 are expected to be zero and $1,213, respectively.

The weighted-average assumptions used to determine pension plan obligations and net periodic benefit costs for the plans are as follows:



	2015				2014				2013
	U.S. Plans		Non-U.S. Plans		U.S. Plans		Non-U.S. Plans		U.S. Plans
Weighted average assumptions used to determine benefit obligations at December 31
Discount rate	4.0	%	2.4	%	3.5	%	1.9	%	4.5	%
Expected return on plan assets	7.0	%	—	%	7.0	%	—	%	7.0	%
Rate of compensation increase	—	%	2.5	%	—	%	2.5	%	4.0	%
Weighted average assumptions used to determine net periodic benefit costs for years ended December 31
Discount rate	3.5	%	1.9	%	4.5	%	2.6	%	3.3	%
Expected return on plan assets	7.0	%	—	%	7.0	%	—	%	7.0	%
Rate of compensation increase	—	%	2.5	%	—	%	2.5	%	4.0	%

The Company's return on asset assumption of 7.0% for its U.S. plans is based on historical asset returns, anticipated future performance of the investments and financial markets and input from the Company's third-party independent actuary and the pension fund trustee. There are no plan assets for the Company's non-U.S. plans. The discount rates for the Company's U.S. and non-U.S. plans are determined using a benchmark pension discount curve and applying spot rates from the curve to each year of expected benefit payments to determine the appropriate discount rate for the Company.

The Company's overall investment strategy for its U.S. plan assets is to achieve a balance between moderate income generation and capital appreciation. The investment strategy includes a mix of approximately 55% of investments for long-term growth and 45% for near-term benefit payments with a diversification of asset types. The Company does not believe that there are significant concentrations of risk in the pension plan assets due to its strategy of asset diversification. The pension fund investment policy allows the pension fund trustee a 10% discretionary range in the asset allocation model, with a target of approximately 55% equity securities and 45% fixed income. The Company expects to maintain the 55/45 investment policy for the near future. Equity securities primarily include investments in large-cap and small-cap companies located in the United States and international developed market stocks. Fixed income securities are comprised of investment grade bonds, including U.S. Treasuries and corporate bonds of companies from diversified industries. At December 31, 2015, plan assets did not include direct ownership of the Company's common stock.

Under the accounting guidance for fair value measurements, inputs used to measure fair value are classified in one of three levels:

Level 1: Quoted market prices in active markets for identical assets or liabilities.

Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data.

Level 3: Unobservable inputs that are not corroborated by market data.

The investments in the bank collective trust funds are valued using a market approach based on the net asset value of units held. The fair values of the Company's U.S. plan assets at December 31, by asset category, are as follows:



	2015				2014
	U.S. Plans				U.S. Plans
	Level 2		Total		Level 2		Total
Bank collective trust funds—Equity securities:
Large-cap index funds ⁽¹⁾	$	18,384	$	18,384	$	19,473	$	19,473
Small-cap index funds ⁽²⁾	4,069		4,069		3,351		3,351
International index funds ⁽³⁾	8,181		8,181		8,474		8,474
Bank collective trust funds—Fixed income:
Bond index funds ⁽⁴⁾	19,624		19,624		21,495		21,495
Short term investment funds	505		505		622		622
	$	50,763	$	50,763	$	53,415	$	53,415

______________________________


(1)	Substantially all of the assets of these funds are invested in large-cap U.S. companies. The remainder of the assets of these funds is invested in cash reserves.


(2)	Substantially all of the assets of these funds are invested in small-cap U.S. companies. The remainder of the assets of these funds is invested in cash reserves.


(3)	Substantially all of the assets of these funds are invested in international companies in developed markets (excluding the United States and Canada). The remainder of the assets of these funds is invested in cash reserves.


(4)	This category represents investment grade bonds of U.S. issuers, including U.S. Treasury notes.

The Company's funding policy for its U.S. plans is consistent with the minimum funding requirements of federal law and regulations, and based on preliminary estimates, the Company expects to make contributions of approximately $900 each for both the salaried and wage pension plans in 2016.

Multi-employer Plans

Non-U.S. Plans

The Company participates in two multi-employer plans, Pensionskasse der Mitarbeiter der Hoechst-Gruppe VVaG and Pensionskasse der Wacker-Chemie GmbH VVaG, which provide benefits to certain of the Company's employees in Germany. These multi-employer plans are closed to new participants. The benefit obligations are covered up to a certain salary threshold by contributions made by the Company and employees to the plans.

Contributions to the Company's multi-employer plans are expensed as incurred and were as follows:



	Year Ended December 31,
	2015		2014
	Non-U.S. Plans		Non-U.S. Plans
Contributions to multi-employer plans ⁽¹⁾	$	4,489	$	2,295

______________________________

(1)

The plan information for both the Pensionskasse der Mitarbeiter der Hoechst-Gruppe VVaG and Pensionskasse der Wacker-Chemie GmbH VVaG plans is publicly available. The plans provide fixed, monthly retirement payments on the basis of the credits earned by the participating employees. To the extent that the plans are underfunded, future contributions to the plans may increase and may be used to fund retirement benefits for employees related to other employers. The Company does not consider either of its multi-employer plans individually significant.

Other Post-retirement Benefits

U.S. Plans

The Company provides post-retirement healthcare benefits to the employees of two subsidiaries who meet certain minimum age and service requirements. The Company has the right to modify or terminate some of these benefits. The following table provides a reconciliation of the benefit obligations of the Company's unfunded post-retirement healthcare plans.



	2015			2014
	U.S. Plans			U.S. Plans
Change in benefit obligation
Benefit obligation, beginning of year	$	20,177		$	19,958
Service cost	22			22
Interest cost	571			733
Actuarial (gain) loss	(1,848		)	989
Benefits paid	(1,107		)	(1,525		)
Benefit obligation, end of year	$	17,815		$	20,177

Change in plan assets
Fair value of plan assets, beginning of year	$	—		$	—
Employer contribution	1,107			1,525
Benefits paid	(1,107		)	(1,525		)
Fair value of plan assets, end of year	$	—		$	—
Funded status, end of year	$	(17,815	)	$	(20,177	)



	2015			2014
	U.S. Plans			U.S. Plans
Amounts recognized in the consolidated balance sheet at December 31
Current liabilities	$	(1,244	)	$	(1,798	)
Noncurrent liabilities	(16,571		)	(18,379		)
Net amount recognized	$	(17,815	)	$	(20,177	)



	2015		2014
	U.S. Plans		U.S. Plans
Amounts recognized in accumulated other comprehensive income
Net loss	$	2,978	$	5,171
Total before tax ⁽¹⁾	$	2,978	$	5,171

______________________________


(1)	After-tax totals for post-retirement healthcare benefits were $1,795 and $3,127 for 2015 and 2014, respectively, and are reflected in stockholders' equity as accumulated other comprehensive loss.

The following table provides the components of net periodic benefit costs, other changes in plan assets and benefit obligation recognized in other comprehensive income.



	Year Ended December 31,
	2015			2014			2013
	U.S. Plans			U.S. Plans			U.S. Plans
Components of net periodic benefit cost
Service cost	$	22		$	22		$	30
Interest cost	571			733			623
Net amortization	345			353			457
Net periodic benefit cost	$	938		$	1,108		$	1,110

Other changes in plan assets and benefit obligation recognized in other comprehensive income (OCI)
Net (gain) loss emerging	$	(1,848	)	$	989		$	(501	)
Amortization of net loss	(345		)	(303		)	(373		)
Amortization of prior service cost	—			(50		)	(84		)
Total recognized in OCI	$	(2,193	)	$	636		$	(958	)
Total net periodic benefit cost and OCI	$	(1,255	)	$	1,744		$	152

The estimated prior service cost and net loss for the post-retirement healthcare benefit plans that will be amortized from accumulated other comprehensive income into net periodic benefit cost during 2016 are expected to be zero and $125, respectively.

The weighted-average assumptions used to determine post-retirement healthcare plan obligations and net periodic benefit costs for the plans are as follows:



	2015		2014		2013
	U.S. Plans		U.S. Plans		U.S. Plans
Weighted average assumptions used to determine benefit obligations at December 31
Discount rate	3.5	%	3.3	%	4.0	%
Weighted average assumptions used to determine net periodic benefit costs for years ended December 31
Discount rate	3.3	%	4.0	%	3.0	%

The discount rate is determined using a benchmark pension discount curve and applying spot rates from the curve to each year of expected benefit payments to determine the appropriate discount rate for the Company. Assumed healthcare trend rates do not have a significant effect on the amounts reported for the healthcare plans because benefits for participants are capped at a fixed amount.

Estimated Future Benefit Payments

The following benefit payments are expected to be paid:



	Pension Benefits		Post- retirement Healthcare
Estimated future benefit payments:
Year 1	$	8,159	$	1,244
Year 2	7,345		1,408
Year 3	7,901		1,409
Year 4	8,461		1,395
Year 5	7,813		1,363
Years 6 to 10	36,897		6,005

Stock-Based Compensation

12 Months Ended

Dec. 31, 2015

Share-based Compensation [Abstract]

Stock-Based Compensation

Under the Westlake Chemical Corporation 2013 Omnibus Incentive Plan (as amended and restated, the "2013 Plan"), all employees and non-employee directors of the Company, as well as certain individuals who have agreed to become the Company's employees, are eligible for awards. Shares of common stock may be issued as authorized in the 2013 Plan. At the discretion of the administrator of the 2013 Plan, employees and non-employee directors may be granted awards in the form of stock options, stock appreciation rights, stock awards, restricted stock units or cash awards (any of which may be a performance award). Outstanding stock option awards have a 10-year term and vest either (1) ratably on an annual basis over a one to four-year period or (2) at the end of a five to 9.5-year period. Current outstanding restricted stock awards vest on the 9.5-year anniversary of the award date. Outstanding restricted stock units vest either (1) ratably on an annual basis over a three-year period or (2) at the end of a one to six-year period. In accordance with accounting guidance related to share-based payments, stock-based compensation expense for all stock-based compensation awards is based on estimated grant-date fair value. The Company recognizes these stock-based compensation costs net of a forfeiture rate and on a straight-line basis over the requisite service period of the award for only those shares expected to vest. For the years ended December 31, 2015, 2014 and 2013, the total recognized stock-based compensation expense related to the 2013 Plan was $10,196, $9,261 and $6,966, respectively.

Option activity and changes during the year ended December 31, 2015 were as follows:



	Options		Weighted Average Exercise Price		Weighted Average Remaining Term (Years)	Aggregate Intrinsic Value
Outstanding at December 31, 2014	1,179,402		$	24.89
Granted	168,369		67.59
Exercised	(32,308	)	32.92
Cancelled	(47,673	)	32.64
Outstanding at December 31, 2015	1,267,790		$	30.07	5.0	$	34,577
Exercisable at December 31, 2015	822,573		$	19.08	4.2	$	29,376

For options outstanding at December 31, 2015, the options had the following range of exercise prices:



Range of Prices	Options Outstanding	Weighted Average Remaining Contractual Life (Years)
$7.12 - $9.65	304,200	2.7
$10.26 - $18.05	349,906	2.6
$22.92 - $30.05	191,292	5.7
$40.38 - $52.35	107,562	7.3
$63.98 - $68.18	314,830	8.7

The aggregate intrinsic value in the table above represents the total pretax intrinsic value (the difference between the Company's closing stock price on the last trading day of the year and the exercise price, multiplied by the number of in-the-money options) that would have been received by the option holders had all option holders exercised their options on December 31, 2015. This amount changes based on the fair market value of the Company's common stock. For the years ended December 31, 2015, 2014 and 2013, the total intrinsic value of options exercised was $1,145, $14,534 and $7,656, respectively.

As of December 31, 2015, $3,755 of total unrecognized compensation cost related to stock options is expected to be recognized over a weighted-average period of 1.3 years. Income tax benefits of $78, $4,512 and $2,224 were realized from the exercise of stock options during the years ended December 31, 2015, 2014 and 2013, respectively.

The Company used the Black-Scholes option pricing model to value its options. The table below presents the weighted average value and assumptions used in determining each option's fair value. Volatility was calculated using historical trends of the Company's common stock price.



	Stock Option Grants
	Year Ended December 31,
	2015			2014			2013
Weighted average fair value	$	20.21		$	20.49		$	17.03
Risk-free interest rate	1.7		%	1.6		%	0.9		%
Expected life in years	5			5			5
Expected volatility	34.2		%	35.7		%	44.5		%
Expected dividend yield	0.9		%	0.7		%	0.6		%

Non-vested restricted stock awards as of December 31, 2015 and changes during the year ended December 31, 2015 were as follows:



	Number of Shares		Weighted Average Grant Date Fair Value
Non-vested at December 31, 2014	205,056		$	24.52
Vested	(124,380	)	30.17
Forfeited	(15,820	)	15.81
Non-vested at December 31, 2015	64,856		$	15.81

As of December 31, 2015, there was $119 of unrecognized stock-based compensation expense related to non-vested restricted stock awards. This cost is expected to be recognized over a weighted-average period of 0.6 years. The total fair value of shares of restricted stock that vested during the years ended December 31, 2015, 2014 and 2013 was $8,363, $8,831 and $12,480, respectively.

Non-vested restricted stock unit as of December 31, 2015 and changes during the year ended December 31, 2015 were as follows:



	Number of Units		Weighted Average Grant Date Fair Value
Non-vested at December 31, 2014	422,000		$	55.75
Granted	100,258		65.77
Vested	(12,277	)	61.08
Forfeited	(11,109	)	56.82
Non-vested at December 31, 2015	498,872		$	57.61

As of December 31, 2015, there was $14,925 of unrecognized stock-based compensation expense related to non-vested restricted stock units. This cost is expected to be recognized over a weighted-average period of 2.5 years. The total fair value of restricted stock units that vested during the years ended December 31, 2015, 2014 and 2013 was $725, $371 and $14, respectively.

Westlake Chemical Partners LP Awards

Our wholly-owned subsidiary and the general partner of Westlake Partners, Westlake Chemical Partners GP LLC ("WLKPGP"), maintains a unit-based compensation plan for directors and employees of WLKPGP and Westlake Partners.

The Westlake Partners 2014 Long-term Incentive Plan ("Westlake Partners 2014 Plan") permits various types of equity awards including but not limited to grants of phantom units and restricted units. Awards granted under the Westlake Partners 2014 Plan may be settled with Westlake Partners units or in cash or a combination thereof. Compensation expense for these awards was not material to our consolidated financial statements for the years ended December 31, 2015 and 2014.

Derivative Commodity Instruments

12 Months Ended

Dec. 31, 2015

Derivative Instruments and Hedges, Assets [Abstract]

Derivative Commodity Instruments

Commodity Risk Management

The Company uses derivative instruments to reduce price volatility risk on commodities, primarily natural gas and ethane, from time to time. The Company does not use derivative instruments to engage in speculative activities.

For derivative instruments that are designated and qualify as fair value hedges, the gains or losses on the derivative instruments, as well as the offsetting losses or gains on the hedged items attributable to the hedged risk, were included in cost of sales in the consolidated statement of operations for the year ended December 31, 2013. The Company had no derivative instruments that were designated as fair value hedges during the years ended December 31, 2015 and 2014.

Gains and losses from changes in the fair value of derivative instruments that are not designated as hedging instruments were included in gross profit in the consolidated statements of operations for the years ended December 31, 2015, 2014 and 2013.

The exposure on commodity derivatives used for price risk management includes the risk that the counterparty will not pay if the market declines below the established fixed price. In such case, the Company would lose the benefit of the derivative differential on the volume of the commodities covered. In any event, the Company would continue to receive the market price on the actual volume hedged. The Company also bears the risk that it could lose the benefit of market improvements over the fixed derivative price for the term and volume of the derivative instruments (as such improvements would accrue to the benefit of the counterparty).

The fair values of derivative instruments in the Company's consolidated balance sheets were as follows:



	Asset Derivatives
	Balance Sheet Location	Fair Value as of December 31,
	Balance Sheet Location	2015		2014
Not designated as hedging instruments
Commodity forward contracts	Accounts receivable, net	$	3,465	$	3,145
Commodity forward contracts	Deferred charges and other assets, net	2,088		—
Total asset derivatives		$	5,553	$	3,145

	Liability Derivatives
	Balance Sheet Location	Fair Value as of December 31,
	Balance Sheet Location	2015		2014
Not designated as hedging instruments
Commodity forward contracts	Accrued liabilities	$	9,325	$	6,549
Commodity forward contracts	Other liabilities	12,437		3,559
Total liability derivatives		$	21,762	$	10,108

The following tables reflect the impact of derivative instruments designated as fair value hedges and the related hedged item on the Company's consolidated statement of operations. There was no material ineffectiveness with regard to the Company's qualifying hedges for the year ended December 31, 2013. The Company had no derivative instruments that were designated as fair value hedges during the years ended December 31, 2015 and 2014.

The impact of derivative instruments that have not been designated as hedges on the Company's consolidated statements of operations were as follows:



Derivatives Not Designated as Hedging Instruments	Location of Gain (Loss) Recognized in Income on Derivative	Year Ended December 31,
Derivatives Not Designated as Hedging Instruments	Location of Gain (Loss) Recognized in Income on Derivative	2015			2014			2013
Commodity forward contracts	Gross profit	$	(11,395	)	$	(9,678	)	$	5,438

See Note 14 for the fair value of the Company's derivative instruments.

Disclosure about Offsetting Asset and Liability Derivatives

Certain of the Company's derivative instruments are executed under an International Swaps and Derivatives Association ("ISDA") Master Agreement, which permits the Company and a counterparty to aggregate the amounts owed by each party under multiple transactions and replace them with a single net amount payable by one party to the other. The following tables present the Company's derivative assets and derivative liabilities reported on the consolidated balance sheets and derivative assets and derivative liabilities subject to enforceable master netting arrangements.



	Derivative Assets as of December 31,
	2015		2014
Derivative assets subject to enforceable master netting arrangements	$	—	$	2,333
Derivative assets not subject to enforceable master netting arrangements	462		111
Total derivative assets	$	462	$	2,444



	December 31, 2015							December 31, 2014
Offsetting of Derivative Assets	Gross Amounts of Recognized Assets		Gross Amounts Offset in the Consolidated Balance Sheet			Net Amounts of Assets Presented in the Consolidated Balance Sheet		Gross Amounts of Recognized Assets		Gross Amounts Offset in the Consolidated Balance Sheet			Net Amounts of Assets Presented in the Consolidated Balance Sheet
Commodity forward contracts	$	5,091	$	(5,091	)	$	—	$	3,034	$	(701	)	$	2,333



	December 31, 2015						December 31, 2014
Derivative Assets by Counterparty	Net Amounts of Assets Presented in the Consolidated Balance Sheet		Gross Amounts Not Offset in the Consolidated Balance Sheet		Net Amount		Net Amounts of Assets Presented in the Consolidated Balance Sheet		Gross Amounts Not Offset in the Consolidated Balance Sheet		Net Amount
Counterparty A	$	—	$	—	$	—	$	2,333	$	—	$	2,333
Total	$	—	$	—	$	—	$	2,333	$	—	$	2,333



	Derivative Liabilities as of December 31,
	2015		2014
Derivative liabilities subject to enforceable master netting arrangements	$	5,803	$	1,490
Derivative liabilities not subject to enforceable master netting arrangements	10,868		7,917
Total derivative liabilities	$	16,671	$	9,407



	December 31, 2015							December 31, 2014
Offsetting of Derivative Liabilities	Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Consolidated Balance Sheet			Net Amounts of Liabilities Presented in the Consolidated Balance Sheet		Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Consolidated Balance Sheet			Net Amounts of Liabilities Presented in the Consolidated Balance Sheet
Commodity forward contracts	$	10,894	$	(5,091	)	$	5,803	$	2,191	$	(701	)	$	1,490



	December 31, 2015						December 31, 2014
Derivative Liabilities by Counterparty	Net Amounts of Liabilities Presented in the Consolidated Balance Sheet		Gross Amounts Not Offset in the Consolidated Balance Sheet		Net Amount		Net Amounts of Liabilities Presented in the Consolidated Balance Sheet		Gross Amounts Not Offset in the Consolidated Balance Sheet		Net Amount
Counterparty A	$	5,564	$	—	$	5,564	$	1,490	$	—	$	1,490
Counterparty B	239		—		239		—		—		—
Total	$	5,803	$	—	$	5,803	$	1,490	$	—	$	1,490

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41620-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624163-113959

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579240-113959

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624177-113959

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80784-113994

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41641-113959

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4H
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624258-113959

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4K
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5708775-113959

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5708773-113959

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5580258-113959

Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4E
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624181-113959

Reference 17: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

Reference 18: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41638-113959

Reference 19: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(n))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Fair Value Measurements

12 Months Ended

Dec. 31, 2015

Fair Value Disclosures [Abstract]

Fair Value Measurements

The Company reports certain assets and liabilities at fair value, which is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). The following tables summarize, by level within the fair value hierarchy, the Company's assets and liabilities at December 31 that were accounted for at fair value on a recurring basis:



	2015
	Level 1			Level 2			Total
Derivative instruments
Risk management assets—Commodity forward contracts	$	5,553		$	—		$	5,553
Risk management liabilities—Commodity forward contracts	(11,648		)	(10,114		)	(21,762		)
Marketable securities
Available-for-sale securities	48,081			520,144			568,225

	2014
	Level 1			Level 2			Total
Derivative instruments
Risk management assets—Commodity forward contracts	$	3,143		$	2		$	3,145
Risk management liabilities—Commodity forward contracts	—			(10,108		)	(10,108		)
Marketable securities
Available-for-sale securities	15,414			—			15,414

The Level 2 measurements for the Company's commodity contracts are derived using forward curves supplied by industry recognized and unrelated third-party services. The Level 2 measurements for the Company's available-for-sale securities are derived using market-based pricing provided by unrelated third-party services.

There were no transfers in and out of Levels 1 and 2 of the fair value hierarchy in 2015 and 2014.

In addition to the assets and liabilities above, the Company has other financial assets and liabilities subject to fair value measures. These financial assets and liabilities include cash and cash equivalents, accounts receivable, net, accounts payable and long-term debt, all of which are recorded at carrying value. The amounts reported in the consolidated balance sheets for cash and cash equivalents, accounts receivable, net and accounts payable approximate their fair value due to the short maturities of these instruments. The carrying and fair values of the Company's long-term debt at December 31, 2015 and 2014 are summarized in the table below. The Company's long-term debt instruments are publicly-traded. A market approach, based upon quotes from financial reporting services, is used to measure the fair value of the Company's long-term debt. Because the Company's long-term debt instruments may not be actively traded, the inputs used to measure the fair value of the Company's long-term debt are classified as Level 2 inputs within the fair value hierarchy.



	2015				2014
	Carrying Value		Fair Value		Carrying Value		Fair Value
3.60% senior notes due 2022	$	249,226	$	244,828	$	249,108	$	248,630
6 ½% senior notes due 2029	100,000		117,153		100,000		116,384
6 ¾% senior notes due 2032	250,000		268,490		250,000		285,545
6 ½% GO Zone Senior Notes Due 2035	89,000		106,491		89,000		106,504
6 ½% IKE Zone Senior Notes Due 2035	65,000		76,741		65,000		77,784
Loan related to tax-exempt waste disposal revenue bonds due 2027	10,889		10,889		10,889		10,889

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Income Taxes

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Income Taxes

The components of income (loss) before income taxes are as follows:



	Year Ended December 31,
	2015		2014			2013
Domestic	$	880,044	$	1,102,101		$	944,378
Foreign	83,397		(18,183		)	(2,206		)
	$	963,441	$	1,083,918		$	942,172

The Company's provision for (benefit from) income taxes consists of the following:



	Year Ended December 31,
	2015		2014			2013
Current
Federal	$	225,617	$	300,610		$	215,903
State	23,966		37,351			22,249
Foreign	9,029		1,974			(137		)
	258,612		339,935			238,015
Deferred
Federal	29,820		40,950			94,471
State	2,807		22,714			(556		)
Foreign	7,157		(4,697		)	(183		)
	39,784		58,967			93,732
Total provision	$	298,396	$	398,902		$	331,747

A reconciliation of taxes computed at the statutory rate to the Company's income tax expense is as follows:



	Year Ended December 31,
	2015			2014			2013
Provision for federal income tax, at statutory rate	$	337,204		$	379,371		$	329,760
State income tax provision, net of federal income tax effect	17,403			40,012			14,364
Foreign income tax rate differential	(13,002		)	3,640			519
Manufacturing deduction	(24,185		)	(24,465		)	(16,275		)
Contingent tax liability	—			(1,626		)	(404		)
Noncontrolling interests	(6,662		)	(2,255		)	—
Other, net	(12,362		)	4,225			3,783
	$	298,396		$	398,902		$	331,747

The tax effects of the principal temporary differences between financial reporting and income tax reporting at December 31 are as follows:



	2015			2014
Net operating loss carryforward	$	17,679		$	18,200
Credit carryforward	746			694
Accruals	62,204			62,845
Allowance for doubtful accounts	4,617			1,998
Inventories	8,663			11,437
Other	7,747			7,660
Deferred taxes assets—total	101,656			102,834
Property, plant and equipment	(423,381		)	(398,683		)
Turnaround costs	(1,467		)	(2,289		)
Basis difference—consolidated partnerships	(200,627		)	(194,480		)
Deferred tax liabilities—total	(625,475		)	(595,452		)
Valuation allowance	(16,345		)	(11,011		)
Total net deferred tax liabilities	$	(540,164	)	$	(503,629	)

Balance sheet classifications
Current deferred tax asset	$	35,439		$	32,437
Noncurrent deferred tax liability	(575,603		)	(536,066		)
Total net deferred tax liabilities	$	(540,164	)	$	(503,629	)

At December 31, 2015, the Company had foreign and state net operating loss carryforwards of approximately $267,192, which will expire in varying amounts between 2016 and 2035 and are subject to certain limitations on an annual basis. Management believes the Company will realize the benefit of a portion of the net operating loss carryforwards before they expire, but to the extent that the full benefit may not be realized, a net operating loss valuation allowance has been recorded. The valuation allowance increased by $5,334 in 2015 due to the creation of additional state and foreign net operating loss carryforwards.

We do not consider the undistributed earnings of our foreign subsidiaries as of December 31, 2015 and 2014 to be permanently reinvested and, accordingly, all required income tax consequences have been considered on such income in accordance with current applicable rules.

The gross unrecognized tax benefits at December 31 are as follows:



	2015		2014
Beginning balance	$	—	$	2,501
Reductions due to statutes of limitations expiring	—		(2,501		)
Ending balance	$	—	$	—

There were no unrecognized tax benefits as of December 31, 2015 and 2014. The Company recognized gross unrecognized tax benefits of $2,501 during the year ended December 31, 2014. The effective income tax rate impact in 2014 was immaterial. The Company recognizes penalties and interest accrued related to unrecognized tax benefits in income tax expense.

The Company files income tax returns in the U.S. federal jurisdiction, various states and foreign jurisdictions. The Company is no longer subject to examinations by tax authorities before the year 2010.

Earnings Per Share

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Earnings Per Share

Earnings per Share

The Company has unvested shares of restricted stock and restricted stock units outstanding that are considered participating securities and, therefore, computes basic and diluted earnings per share under the two-class method. Basic earnings per share for the periods are based upon the weighted average number of shares of common stock outstanding during the periods. Diluted earnings per share include the effect of certain stock options.



	Year Ended December 31,
	2015			2014			2013
Net income attributable to Westlake Chemical Corporation	$	646,010		$	678,523		$	610,425
Less:
Net income attributable to participating securities	(2,825		)	(1,502		)	(2,562		)
Net income attributable to common shareholders	$	643,185		$	677,021		$	607,863

The following table reconciles the denominator for the basic and diluted earnings per share computations shown in the consolidated statements of operations:



	Year Ended December 31,
	2015		2014		2013
Weighted average common shares—basic ⁽¹⁾	131,823,707		133,111,230		133,224,256
Plus incremental shares from:
Assumed exercise of options ⁽¹⁾	478,105		532,184		554,994
Weighted average common shares—diluted ⁽¹⁾	132,301,812		133,643,414		133,779,250

Earnings per common share attributable to Westlake Chemical Corporation: ⁽¹⁾
Basic	$	4.88	$	5.09	$	4.57
Diluted	$	4.86	$	5.07	$	4.55

______________________________


(1)	Share amounts and per share data for the year ended December 31, 2013 have been restated to reflect the effect of a two-for-one stock split on March 18, 2014. See Note 9 for additional information.

Excluded from the computation of diluted earnings per share for the years ended December 31, 2015, 2014 and 2013 are options to purchase 301,969, 126,091 and 119,452 shares of common stock, respectively. These options were outstanding during the periods reported but were excluded because the effect of including them would have been antidilutive.

Supplemental Information

12 Months Ended

Dec. 31, 2015

Supplemental Information

Accrued Liabilities

Accrued liabilities were $287,313 and $276,118 at December 31, 2015 and 2014, respectively. Accrued rebates and accrued incentive compensation, which are components of accrued liabilities, were $46,460 and $41,168 at December 31, 2015, respectively, and $49,900 and $37,626 at December 31, 2014, respectively. No other component of accrued liabilities was more than five percent of total current liabilities.

Other Liabilities

Other liabilities were $150,961 and $174,859 at December 31, 2015 and 2014, respectively. Non-current pension obligation, which is a component of other liabilities, was $106,250 and $136,296 at December 31, 2015 and 2014, respectively. No other component of other liabilities was more than five percent of total liabilities.

Other Income (Expense), Net

The components of other income (expense), net are as follows:



	Year Ended December 31,
	2015			2014			2013
Interest income	$	6,034		$	3,468		$	3,086
Dividend income	3,559			532			—
Foreign exchange currency gains (losses), net ⁽¹⁾	1,828			(7,382		)	(1,375		)
Income from equity method investments	6,242			5,883			4,914
Impairment of equity method investments	(4,925		)	(6,747		)	—
Gain on acquisition and related expenses, net	20,430			—			—
Gains (losses) from sales of securities, net	3,798			1,212			(19		)
Other	1,304			313			184
Other income (expense), net	$	38,270		$	(2,721	)	$	6,790

______________________________


(1)	Aggregate foreign exchange currency gains and losses included in the consolidated statements of operations for the years ended December 31, 2015, 2014 and 2013.

Cash Flow Information



	Year Ended December 31,
	2015		2014		2013
Cash paid for:
Interest paid, net of interest capitalized	$	31,946	$	35,336	$	16,426
Income taxes paid	314,186		314,745		251,599

Supplemental Noncash Investing Activities

In conjunction with the acquisitions discussed in Note 21, liabilities assumed consist of the following:



	Year Ended December 31,
	2015			2014
Fair value of assets acquired	$	44,013		$	961,823
Fair value of investment before business combination, net of preexisting balances	(10,352		)	—
Noncontrolling interest acquired	(1,597		)	—
Cash paid	(5,518		)	(736,224		)
Liabilities assumed	$	26,546		$	225,599

Related Party And Affiliate Transactions	12 Months Ended
Related Party And Affiliate Transactions	Dec. 31, 2015
Related Party Transactions [Abstract]
Related Party And Affiliate Transactions	Related Party and Affiliate Transactions The Company leases office space for management and administrative services from an affiliate of the Company's principal stockholder. For the years ended December 31, 2015, 2014 and 2013, the Company incurred lease payments of approximately $2,148, $2,001 and $1,614, respectively. The amount payable to this affiliate was $196 and $179 at December 31, 2015 and 2014, respectively. Cypress Interstate Pipeline L.L.C., a natural gas liquids pipeline joint venture company in which the Company owns a 50% equity stake, transports natural gas liquid feedstocks to the Company's Lake Charles complex through its pipeline. For the years ended December 31, 2015, 2014 and 2013, the Company incurred pipeline fees of approximately $14,110, $14,206 and $13,328, respectively, payable to this joint venture for usage of the pipeline. The amount payable to this joint venture was $991 at December 31, 2015. There were no outstanding amounts due to this joint venture at December 31, 2014. EPS Ethylene Pipeline Süd GmbH & Co. KG, an ethylene pipeline company in which the Company owns a 10% equity stake, transports ethylene feedstocks to the Company's Gendorf, Germany production facility through its pipeline. For the years ended December 31, 2015 and 2014, the Company incurred pipeline fees of approximately $1,022 and $548, respectively, for usage of the pipeline. There were no outstanding amounts due to this related party at December 31, 2015. The amount payable to this related party was $12 at December 31, 2014. The Company owns a 15% and an 11% equity stake in InfraServ Knapsack GmbH & Co. KG and InfraServ Gendorf GmbH & Co. KG, respectively. The Company has service agreements with these entities, including contracts to provide electricity and technical services to certain of the Company's production facilities in Germany. For the years ended December 31, 2015 and 2014, the Company incurred charges aggregating approximately $115,961 and $55,400, respectively, for these services. The amounts payable to these related parties were $22,931 and $14,161 at December 31, 2015 and 2014, respectively. Dividends received from equity method investments were $5,610, $5,459 and $5,114 for the years ended December 31, 2015, 2014 and 2013, respectively. One of our directors serves as Chairman and Chief Executive Officer of American Air Liquide Holdings, Inc. and as a Senior Vice President of the Air Liquide Group. The Company purchased oxygen, nitrogen and utilities and leased cylinders from various affiliates of American Air Liquide Holdings, Inc. ("Air Liquide") aggregating approximately $10,345, $13,862 and $16,407 for the years ended December 31, 2015, 2014 and 2013, respectively. The amount payable to Air Liquide was $762 at December 31, 2015. There were no outstanding amounts due to Air Liquide at December 31, 2014.

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

Insurance Recovery	12 Months Ended
Insurance Recovery	Dec. 31, 2015
Insurance Recovery [Abstract]
Insurance Recovery	Insurance Recovery During the second and third quarters of 2015, the Company's production rates and operating costs at its Knapsack, Germany and Cologne, Germany facilities were negatively impacted due to an interruption of feedstock supply as a result of a fire at a third-party supplier's ethylene production facility. For the year ended December 31, 2015, the Company recognized approximately $7,809 as a partial insurance recovery related to business interruption costs, primarily for additional costs incurred to procure the necessary feedstock and other costs as a result of the fire at the third-party facility. The partial insurance recovery is included in cost of sales in the consolidated statement of operations.

Westlake Chemical Partners LP

12 Months Ended

Dec. 31, 2015

Westlake Chemical Partners LP

Westlake Partners is a publicly traded master limited partnership that was formed by the Company to operate, acquire and develop facilities for the processing of natural gas liquids and related assets.

Initial Public Offering of Westlake Partners

On August 4, 2014, Westlake Partners completed its initial public offering of 12,937,500 common units at a price of $24.00 per unit, which included 1,687,500 units purchased by the underwriters pursuant to the exercise in full of their over-allotment option. Net proceeds to Westlake Partners from the sale of the units was approximately $286,088, net of underwriting discounts, structuring fees and offering expenses (the "Offering Costs") of approximately $24,412. At the time of the initial public offering, Westlake Partners' assets consisted of a 10.6% limited partner interest in Westlake Chemical OpCo LP ("OpCo"), as well as the general partner interest in OpCo. At the time of the initial public offering, the Company retained an 89.4% limited partner interest in OpCo, a 52.2% limited partner interest in Westlake Partners (common and subordinated units), a general partner interest in Westlake Partners and incentive distribution rights. The Company consolidates Westlake Partners for financial reporting purposes as the Company has a controlling financial interest. The initial public offering represented the sale of 47.8% of the common units in Westlake Partners. OpCo used the net proceeds from the purchase of its limited partner interest to establish a cash reserve of approximately $55,419 for turnaround expenditures, to reimburse approximately $151,729 for capital expenditures incurred by the Company with respect to certain of the assets contributed to OpCo and to repay intercompany debt to the Company of approximately $78,940.

The following table is a reconciliation of proceeds from the initial public offering:



Total proceeds from the initial public offering	$	310,500
Less: Offering Costs	(24,412		)
Net proceeds from the initial public offering	286,088
Less: Cash retained by OpCo	(55,419		)
Net proceeds distributed to the Company from the initial public offering	$	230,669

Acquisitions

12 Months Ended

Dec. 31, 2015

Business Combinations [Abstract]

Acquisitions

Suzhou Huasu Plastics Co., Ltd.

On June 1, 2015, the Company acquired an additional 35.7% equity interest in Suzhou Huasu Plastics Co., Ltd. ("Huasu") from INEOS Chlor Vinyls Holdings B.V., increasing its interest in Huasu to 95.0%. Huasu is a polyvinyl chloride ("PVC") joint venture based near Shanghai, in the People's Republic of China and has a combined annual capacity of 300 million pounds of PVC resin and 145 million pounds of PVC film and sheet.

Prior to the acquisition of this 35.7% interest, the Company owned a 59.3% interest in Huasu. The Company accounted for the investment using the equity method of accounting because Huasu did not meet the definition of a variable interest entity and because contractual arrangements giving certain substantive participatory rights to minority shareholders prevented the Company from exercising a controlling financial interest over Huasu. As a result of the Company obtaining control over Huasu, the Company's 59.3% interest was remeasured to fair value, resulting in a loss of $1,505, which is included in other income (expense), net in the consolidated statement of operations.

The closing date purchase price of $5,518 was paid with available cash on hand. The acquisition is being accounted for under the acquisition method of accounting. The transaction resulted in a bargain purchase acquisition-date gain of $22,550 and is recognized in other income (expense), net in the consolidated statement of operations. The Company believes there are several factors that contributed to this transaction resulting in a bargain purchase acquisition-date gain, including the slowdown in the growth of, and current weakness in, the Chinese economy. The assets acquired and liabilities assumed and the results of operations of this acquired business are included in the Vinyls segment. Huasu's net sales and earnings included in the consolidated statement of operations since the acquisition date have not been presented separately as they are not material to the Company's consolidated statement of operations for the year ended December 31, 2015. The acquisition-related costs recognized in the consolidated statement of operations for the year ended December 31, 2015 are not material. The pro forma impact of this business combination has not been presented as it is not material to the Company's consolidated statements of operations for the years ended December 31, 2015 and 2014.

The following table summarizes the consideration transferred and the estimated fair value of identified assets acquired and liabilities assumed at the date of acquisition. The final determination of fair value for certain assets and liabilities will be completed as soon as the information necessary to complete the analysis is obtained. These amounts will be finalized as soon as possible, but no later than one year from the acquisition date.



Fair value of consideration transferred—cash	$	5,518
Preexisting balances between the Company and Huasu, net	(8,538		)
Fair value of the Company's investment in Huasu before the business combination ⁽¹⁾	18,890
Fair value of the noncontrolling interest in Huasu ⁽¹⁾	1,597
	$	17,467

Preliminary allocation of consideration transferred to net assets acquired:
Cash	$	21,300
Working capital, excluding inventory and cash ⁽²⁾	(5,461		)
Inventories	17,717
Property, plant and equipment	19,786
Other assets	7,760
Notes payable to banks	(21,085		)
Total identifiable net assets	40,017
Bargain purchase gain on acquisition	$	22,550

______________________________


(1)	The fair values of the Company's 59.3% equity interest and the noncontrolling interest were estimated using internally developed, unobservable inputs (Level 3 inputs in the fair value hierarchy of fair value accounting) based on a cost approach.


(2)	The fair value of accounts receivable acquired is $2,515, with the gross contractual amount being $3,006. The Company expects $491 to be uncollectible.

Vinnolit Holdings GmbH and Subsidiary Companies

On July 31, 2014, the Company acquired all the equity interests in German-based Vinnolit Holdings GmbH and its subsidiary companies ("Vinnolit") from several entities associated with Advent International Corporation (the "Sellers"). Vinnolit is headquartered in Ismaning, Germany and is an integrated global leader in specialty PVC resins, with a combined annual capacity of 1.7 billion pounds of PVC, including specialty paste and suspension grades, 1.5 billion pounds of vinyl chloride monomer ("VCM") and 1.0 billion pounds of caustic soda. The Vinnolit acquisition included six production facilities located in Burghausen, Gendorf, Cologne, Knapsack and Schkopau in Germany and Hillhouse in the United Kingdom. The Company also acquired Vinnolit's technical centers, including a research and development facility in Gendorf and an applications laboratory in Burghausen. The Company's management believes that this strategic acquisition will enhance its strategy of integration and expansion into new markets and specialty products, in addition to growing the Company's global presence with a footprint in Europe and surrounding markets.

The purchase price of $736,224 was paid with available cash on hand. The acquisition is being accounted for under the acquisition method of accounting. The assets acquired and liabilities assumed and the results of operations of this acquired business are included in the Vinyls segment.

The acquired business contributed net sales and net loss of $431,407 and $3,718, respectively, to the Company for the period from July 31, 2014 to December 31, 2014. The following unaudited consolidated pro forma information presents consolidated information as if the acquisition had occurred on January 1, 2013:



	Pro Forma Year Ended December 31,
	2014		2013
Net sales	$	5,152,806	$	4,976,998

Net income	$	737,913	$	666,202
Net income attributable to noncontrolling interests	6,493		—
Net income attributable to Westlake Chemical Corporation	$	731,420	$	666,202
Earnings per common share attributable to Westlake Chemical Corporation:
Basic	$	5.48	$	4.98
Diluted	$	5.46	$	4.96

The pro forma amounts above have been calculated after applying the Company's accounting policies and adjusting the Vinnolit results to reflect (1) the additional depreciation and amortization that would have been charged assuming the fair value adjustments to property, plant and equipment and intangible assets had been applied from January 1, 2013; (2) the elimination of interest expense assuming the long-term debt paid off on behalf of the Sellers as of the acquisition date had been retired as of January 1, 2013; (3) the elimination of transaction-related costs; and (4) an adjustment to tax-effect the aforementioned pro forma adjustments using an estimated aggregate statutory income tax rate of the jurisdictions to which the above adjustments relate. The pro forma amounts do not include any potential synergies, cost savings or other expected benefits of the Vinnolit acquisition, are presented for illustrative purposes only and are not necessarily indicative of results that would have been achieved if the acquisition had occurred as of January 1, 2013 or of future operating performance.

For the year ended December 31, 2014, the Company recognized $13,427 of transaction-related costs. These costs are included in general and administrative expenses and other income (expense), net in the consolidated statement of operations for the year ended December 31, 2014. The transaction-related costs included in other income (expense), net pertained to losses incurred on forward foreign exchange contracts for the purchase consideration of Vinnolit.

The following table summarizes the purchase consideration transferred and the fair value of identified assets acquired and liabilities assumed at the date of acquisition. As the fair value of the net assets acquired equals consideration paid, no goodwill was recorded.



Fair value of consideration transferred:
Cash paid to Sellers	$	309,619
Cash deposited in escrow ⁽¹⁾	13,390
Retirement of long-term debt as of July 31, 2014, on behalf of the Sellers ⁽²⁾	413,215
Total purchase consideration	$	736,224

Allocation of consideration transferred to net assets acquired:
Cash	$	125,137
Working capital, excluding inventory and cash ⁽³⁾	15,373
Inventories ⁽⁴⁾	114,961
Property, plant and equipment	469,484
Investments	51,552
Other assets ⁽⁵⁾	76,828
Intangible assets:
Trademarks and trade name (weighted average life of 20 years)	40,170
Developed technologies (weighted average life of 20 years)	31,600
Other intangibles (weighted average life of 9.4 years)	1,422
Deferred income tax asset—current	7,909
Deferred income tax asset—non-current	27,387
Pension obligation	(117,970		)
Other long-term liabilities	(10,723		)
Power purchase agreement liability ⁽⁶⁾	(10,826		)
Deferred income tax liability—current	(6,845		)
Deferred income tax liability—non-current	(79,235		)
Total identifiable net assets	736,224
Goodwill ⁽⁷⁾	—
Consideration transferred	$	736,224

______________________________


(1)	None of the cash held in escrow is considered contingent consideration as it is expected to be released to the Sellers pending the Sellers' satisfaction of general representations and warranties made in connection with the execution of the purchase agreement.


(2)	Vinnolit's long-term debt paid on behalf of the Sellers was not legally assumed by Westlake in the acquisition and the retirement was a condition of the consummation of the purchase agreement. Therefore, the retirement has been included in the total purchase consideration.


(3)	The fair value of accounts receivable acquired is $181,890, with the gross contractual amount being $183,833. The Company expects $1,943 to be uncollectable.


(4)	An adjustment of approximately $16,900 was recorded to reflect Vinnolit's inventories at fair value and increased cost of sales by the same amount for the year ended December 31, 2014.


(5)	Included in other assets was a loan acquired that was repaid prior to December 31, 2014.


(6)	A liability arising from the unfavorable forward purchase contracts for the purchase of power was recognized at fair value. This liability will be amortized over a period of approximately three years, being the weighted-average life of the forward purchase contracts.


(7)	As the fair value of the net assets acquired equals consideration paid, no goodwill was recorded.

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1497-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1490-128463

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1486-128463

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1500-128463

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1524-128463

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7000-128479

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4922-128472

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4934-128472

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4926-128472

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1383-128463

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6996-128479

Commitments and Contingencies Disclosure [Abstract]

Commitments And Contingencies

12 Months Ended

Dec. 31, 2015

Commitments And Contingencies

Commitments and Contingencies

The Company is subject to environmental laws and regulations that can impose civil and criminal sanctions and that may require it to mitigate the effects of contamination caused by the release or disposal of hazardous substances into the environment. Under one law, the U.S. Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA"), an owner or operator of property may be held strictly liable for remediating contamination without regard to whether that person caused the contamination, and without regard to whether the practices that resulted in the contamination were legal at the time they occurred. Because several of the Company's production sites have a history of industrial use, it is impossible to predict precisely what effect these legal requirements will have on the Company.

European Regulations. Under the Industrial Emission Directive ("IED"), European Union member state governments are expected to adopt rules and implement environmental permitting programs relating to air, water and waste for industrial facilities. In this context, concepts such as BAT ("best available technique") are being explored. Future implementation of these concepts may result in technical modifications in the Company's European facilities. In addition, under the Environmental Liability Directive, European Union member states can require the remediation of soil and groundwater contamination in certain circumstances, under the "polluter pays principle." The Company is unable to predict the impact these requirements and concepts may have on its future costs of compliance.

Contract Disputes with Goodrich and PolyOne. In connection with the 1990 and 1997 acquisitions of the Goodrich Corporation ("Goodrich") chemical manufacturing facility in Calvert City, Goodrich agreed to indemnify the Company for any liabilities related to preexisting contamination at the site. For its part, the Company agreed to indemnify Goodrich for post-closing contamination caused by the Company's operations. The soil and groundwater at the site, which does not include the Company's nearby PVC facility, had been extensively contaminated under Goodrich's operations. In 1993, Goodrich spun off the predecessor of PolyOne Corporation ("PolyOne"), and that predecessor assumed Goodrich's indemnification obligations relating to preexisting contamination.

In 2003, litigation arose among the Company, Goodrich and PolyOne with respect to the allocation of the cost of remediating contamination at the site. The parties settled this litigation in December 2007 and the case was dismissed. In the settlement the parties agreed that, among other things: (1) PolyOne would pay 100% of the costs (with specified exceptions), net of recoveries or credits from third parties, incurred with respect to environmental issues at the Calvert City site from August 1, 2007 forward; (2) either the Company or PolyOne might, from time to time in the future (but not more than once every five years), institute an arbitration proceeding to adjust that percentage; and (3) the Company and PolyOne would negotiate a new environmental remediation utilities and services agreement to cover the Company's provision to, or on behalf of, PolyOne of certain environmental remediation services at the site. The current environmental remediation activities at the Calvert City site do not have a specified termination date but are expected to last for the foreseeable future. The costs incurred by the Company that have been invoiced to PolyOne to provide the environmental remediation services were $2,210, $2,805 and $3,284 for the years ended December 31, 2015, 2014 and 2013, respectively. By letter dated March 16, 2010, PolyOne notified the Company that it was initiating an arbitration proceeding under the settlement agreement. In this proceeding, PolyOne sought to readjust the percentage allocation of costs and to recover approximately $1,400 from the Company in reimbursement of previously paid remediation costs. In December 2015, the arbitration panel dismissed the proceeding with prejudice. In a separate proceeding in Ohio state court, the Company is seeking certain insurance documents from PolyOne.

State Administrative Proceedings. There are several administrative proceedings in Kentucky involving the Company, Goodrich and PolyOne related to the same manufacturing site in Calvert City. In 2003, the Kentucky Environmental and Public Protection Cabinet (the "Cabinet") re-issued Goodrich's Resource Conservation and Recovery Act ("RCRA") permit which requires Goodrich to remediate contamination at the Calvert City manufacturing site. Both Goodrich and PolyOne challenged various terms of the permit in an attempt to shift Goodrich's clean-up obligations under the permit to the Company. The Company intervened in the proceedings. The Cabinet has suspended all corrective action under the RCRA permit in deference to a remedial investigation and feasibility study ("RIFS") being conducted, under the auspices of the U.S. Environmental Protection Agency ("EPA"), pursuant to an Administrative Settlement Agreement ("AOC"), which became effective on December 9, 2009. See "Federal Administrative Proceedings" below. The proceedings have been postponed. Periodic status conferences will be held to evaluate whether additional proceedings will be required.

Federal Administrative Proceedings. In May 2009, the Cabinet sent a letter to the EPA requesting the EPA's assistance in addressing contamination at the Calvert City site under CERCLA. In its response to the Cabinet also in May 2009, the EPA stated that it concurred with the Cabinet's request and would incorporate work previously conducted under the Cabinet's RCRA authority into the EPA's cleanup efforts under CERCLA. Since 1983, the EPA has been addressing contamination at an abandoned landfill adjacent to the Company's plant which had been operated by Goodrich and which was being remediated pursuant to CERCLA. The EPA has directed Goodrich and PolyOne to conduct additional investigation activities at the landfill and at the Company's plant. In June 2009, the EPA notified the Company that the Company may have potential liability under section 107(a) of CERCLA at its plant site. Liability under section 107(a) of CERCLA is strict and joint and several. The EPA also identified Goodrich and PolyOne, among others, as potentially responsible parties at the plant site. The Company negotiated, in conjunction with the other potentially responsible parties, an AOC and an order to conduct a RIFS. On July 12, 2013, the parties submitted separate draft RIFS reports to the EPA. The EPA has hired a contractor to complete the remedial investigation report.

Monetary Relief. Except as noted above with respect to the settlement of the contract litigation among the Company, Goodrich and PolyOne, none of the court, the Cabinet nor the EPA has established any allocation of the costs of remediation among the various parties that are involved in the judicial and administrative proceedings discussed above. At this time, the Company is not able to estimate the loss or reasonable possible loss, if any, on the Company's financial statements that could result from the resolution of these proceedings. Any cash expenditures that the Company might incur in the future with respect to the remediation of contamination at the site would likely be spread out over an extended period. As a result, the Company believes it is unlikely that any remediation costs allocable to it will be material in terms of expenditures made in any individual reporting period.

Potential Flare Modifications. For several years, the EPA has been conducting an enforcement initiative against petroleum refineries and petrochemical plants with respect to emissions from flares. A number of companies have entered into consent agreements with the EPA requiring both modifications to reduce flare emissions and the installation of additional equipment to better track flare operations and emissions. On April 21, 2014, the Company received a Clean Air Act Section 114 Information Request from the EPA which sought information regarding flares at the Calvert City and Lake Charles facilities. The EPA has informed the Company that the information provided leads the EPA to believe that some of the flares are out of compliance with applicable standards. The EPA has demanded that the Company conduct additional flare sampling and provide supplemental information. The Company is currently in negotiations with the EPA regarding these demands. The EPA has indicated that it is seeking a consent decree that would obligate the Company to take corrective actions relating to the alleged noncompliance. The Company has not agreed that any flares are out of compliance or that any corrective actions are warranted. Depending on the outcome of the Company's negotiations with the EPA, additional controls on emissions from its flares may be required and these could result in increased capital and operating costs.

Louisiana Notice of Violations. The Louisiana Department of Environmental Quality ("LDEQ") has issued notices of violations ("NOVs") regarding the Company's assets for various air compliance issues. The Company is working with LDEQ to settle these claims, and a global settlement of all claims is being discussed. The Company has reached a verbal agreement with the LDEQ to settle certain of the NOVs in two separate settlements for a combined $192 in civil penalties. The Company does not believe that any settlements for the remaining NOVs will have a material adverse effect on the Company's financial condition, results of operations or cash flows.

In addition to the matters described above, the Company is involved in various legal proceedings incidental to the conduct of its business. The Company does not believe that any of these legal proceedings will have a material adverse effect on its financial condition, results of operations or cash flows.

Other Commitments

The Company is obligated under various long-term and short-term noncancelable operating leases, primarily related to rail car leases and land. Several of the leases provide for renewal terms and, in certain leases, purchase options. At December 31, 2015, future minimum lease commitments for operating lease obligations and capital lease obligations were as follows:



	Operating Leases		Capital Leases
2016	$	43,200	$	245
2017	42,293		245
2018	35,119		245
2019	29,164		245
2020	24,124		245
Thereafter	582,327		779
Total minimum lease payments	$	756,227	$	2,004
Less: Imputed interest costs			(519		)
Present value of net minimum lease payments			$	1,485

Operating lease rental expense was approximately $69,455, $56,014 and $45,361 for the years ended December 31, 2015, 2014 and 2013, respectively.

The Company has various unconditional purchase obligations, primarily to purchase goods and services, including commitments to purchase various utilities, feedstock, nitrogen, oxygen, product storage and pipeline usage. Unrecorded unconditional purchase obligations for the next five years are as follows: $184,581, $194,434, $176,230, $149,194 and $141,352 in 2016, 2017, 2018, 2019 and 2020, respectively.

Segment And Geographic Information

12 Months Ended

Dec. 31, 2015

Segment Reporting [Abstract]

Segment and Geographic Information

Segment Information

The Company operates in two principal operating segments: Olefins and Vinyls. These segments are strategic business units that offer a variety of different products. The Company manages each segment separately as each business requires different technology and marketing strategies.

The Company's Olefins segment manufactures and markets polyethylene, styrene monomer and various ethylene co-products. The Company's ethylene production is used in the Company's polyethylene, styrene and vinyl chloride monomer ("VCM") operations. In addition, the Company sells ethylene and ethylene co-products, primarily propylene, crude butadiene, pyrolysis gasoline and hydrogen, to external customers.

The majority of sales in the Company's Olefins business are made under long-term agreements where contract volumes are established within a range (typically, more than one year). Earlier terminations may occur if the parties fail to agree on price and deliveries are suspended for a period of several months. In most cases, these contracts also contemplate extension of the term unless specifically terminated by one of the parties. No single customer accounted for more than 10% of sales in the Olefins segment for the years ended December 31, 2015, 2014 or 2013.

The Company's Vinyls segment manufactures and markets PVC, VCM, EDC, chlorine, caustic soda and ethylene. The Company also manufactures and sells products fabricated from PVC that the Company produces, including pipe, fittings, profiles, foundation building products, fence and deck components, window and door components and film and sheet products. The Company's main North American chemical manufacturing facilities are located in Calvert City and Geismar, Louisiana. The Company also has five manufacturing sites in Germany, one manufacturing site in the United Kingdom and one manufacturing site in the People's Republic of China.

As of December 31, 2015, the Company owned 11 building products plants. The Company uses its chlorine, VCM and PVC production to manufacture its building products. No single customer accounted for more than 10% of sales in the Vinyls segment for the years ended December 31, 2015, 2014 or 2013.

The accounting policies of the individual segments are the same as those described in Note 1.



	Year Ended December 31,
	2015			2014			2013
Net external sales
Olefins
Polyethylene	$	1,650,964		$	1,922,535		$	1,750,292
Styrene, feedstock and other	609,149			801,155			803,377
Total olefins	2,260,113			2,723,690			2,553,669
Vinyls
PVC, caustic soda and other	1,718,359			1,203,332			800,658
Building products	484,864			488,328			405,157
Total vinyls	2,203,223			1,691,660			1,205,815
	$	4,463,336		$	4,415,350		$	3,759,484

Intersegment sales
Olefins	$	106,861		$	146,539		$	320,909
Vinyls	1,493			1,385			1,502
	$	108,354		$	147,924		$	322,411

Income (loss) from operations
Olefins	$	747,436		$	1,013,825		$	833,249
Vinyls	254,452			142,740			154,684
Corporate and other	(42,061		)	(32,574		)	(34,469		)
	$	959,827		$	1,123,991		$	953,464

Depreciation and amortization
Olefins	$	110,684		$	106,244		$	102,938
Vinyls	134,546			101,666			54,371
Corporate and other	527			576			499
	$	245,757		$	208,486		$	157,808

Other income (expense), net
Olefins	$	4,656		$	6,102		$	7,410
Vinyls	8,540			2,680			(1,858		)
Corporate and other	25,074			(11,503		)	1,238
	$	38,270		$	(2,721	)	$	6,790

Provision for (benefit from) income taxes
Olefins	$	242,516		$	354,159		$	288,214
Vinyls	64,456			52,249			48,296
Corporate and other	(8,576		)	(7,506		)	(4,763		)
	$	298,396		$	398,902		$	331,747

Capital expenditures
Olefins	$	304,873		$	188,729		$	145,542
Vinyls	176,582			237,992			531,939
Corporate and other	9,971			4,383			1,741
	$	491,426		$	431,104		$	679,222



	December 31, 2015		December 31, 2014
Total assets
Olefins	$	1,869,888	$	1,785,895
Vinyls	2,638,833		2,618,646
Corporate and other	1,066,531		809,449
	$	5,575,252	$	5,213,990

A reconciliation of total segment income from operations to consolidated income before income taxes is as follows:



	Year Ended December 31,
	2015			2014			2013
Income from operations for reportable segments	$	959,827		$	1,123,991		$	953,464
Interest expense	(34,656		)	(37,352		)	(18,082		)
Other income (expense), net	38,270			(2,721		)	6,790
Income before income taxes	$	963,441		$	1,083,918		$	942,172

Geographic Information



	Year Ended December 31,
	2015		2014		2013
Sales to external customers ⁽¹⁾
United States	$	3,133,395	$	3,596,091	$	3,404,378
Foreign
Germany	394,459		198,921		3,942
Canada	195,790		217,567		214,162
Switzerland	106,750		89,214		54,637
Italy	90,237		36,823		55
France	58,727		27,521		8,207
Other	483,978		249,213		74,103
	$	4,463,336	$	4,415,350	$	3,759,484



	December 31, 2015		December 31, 2014
Long-lived assets
United States	$	2,588,366	$	2,319,572
Foreign
Germany	379,262		417,702
Other	36,439		20,283
	$	3,004,067	$	2,757,557

______________________________


(1)	Revenues are attributed to countries based on location of customer.

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8981-108599

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e9038-108599

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8971-108599

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8595-108599

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8380-108599

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8933-108599

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 26
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8844-108599

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8984-108599

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e9031-108599

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e9054-108599

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8538-108599

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 29
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8864-108599

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8924-108599

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=51669610&loc=d3e8906-108599

Quarterly Financial Information Disclosure [Abstract]

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Subsequent events were evaluated through the date on which the financial statements were issued.

Guarantor Disclosures	12 Months Ended
Guarantor Disclosures	Dec. 31, 2015
Guarantor Disclosures [Abstract]
Guarantor Disclosures	Guarantor Disclosures The Company's payment obligations under the 3.60% senior notes due 2022 are fully and unconditionally guaranteed by each of its current and future domestic subsidiaries that guarantee other debt of the Company or of another guarantor of the 3.60% senior notes due 2022 in excess of $5,000 (the "Guarantor Subsidiaries"). Except for OpCo, which is less than 100% owned, each Guarantor Subsidiary is 100% owned by Westlake Chemical Corporation (the "100% Owned Guarantor Subsidiaries"). See Note 20 regarding Westlake Partners' 10.6% limited partnership interest in OpCo. The initial public offering of Westlake Partners resulted in OpCo ceasing to be a 100% owned subsidiary of the Company. OpCo has been presented as a less than 100% owned guarantor subsidiary in each of the tables below, including for periods prior to the initial public offering of Westlake Partners. These guarantees are the joint and several obligations of the Guarantor Subsidiaries. The following unaudited condensed consolidating financial information presents the financial condition, results of operations and cash flows of Westlake Chemical Corporation, the 100% owned Guarantor Subsidiaries, OpCo and the remaining subsidiaries that do not guarantee the 3.60% senior notes due 2022 (the "Non-Guarantor Subsidiaries"), together with consolidating eliminations necessary to present the Company's results on a consolidated basis.

Quarterly Financial Information

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information

Quarterly Financial Information (Unaudited)



	Three Months Ended
	March 31, 2015		June 30, 2015		September 30, 2015		December 31, 2015
Net sales	$	1,103,531	$	1,185,002	$	1,188,037	$	986,766
Gross profit	284,546		353,181		311,276		236,188
Income from operations	229,280		295,374		254,028		181,145
Net income attributable to Westlake Chemical Corporation	146,342		205,095		183,604		110,969
Earnings per common share attributable to Westlake Chemical Corporation: ⁽¹⁾
Basic	$	1.10	$	1.55	$	1.39	$	0.85
Diluted	$	1.10	$	1.54	$	1.39	$	0.84

	Three Months Ended
	March 31, 2014		June 30, 2014		September 30, 2014		December 31, 2014
Net sales	$	1,027,676	$	998,576	$	1,253,227	$	1,135,871
Gross profit	287,010		305,971		361,520		362,849
Income from operations	248,055		266,788		306,761		302,387
Net income attributable to Westlake Chemical Corporation	158,032		169,443		167,757		183,291
Earnings per common share attributable to Westlake Chemical Corporation: ⁽¹⁾
Basic	$	1.18	$	1.27	$	1.26	$	1.38
Diluted	$	1.18	$	1.26	$	1.25	$	1.37

______________________________


(1)	Basic and diluted earnings per common share ("EPS") for each quarter is computed using the weighted average shares outstanding during that quarter, while EPS for the year is computed using the weighted average shares outstanding for the year. As a result, the sum of the EPS for each of the four quarters may not equal the EPS for the year.

Valuation and Qualifying Accounts

12 Months Ended

Dec. 31, 2015

Valuation and Qualifying Accounts [Abstract]

Valuation and Qualifying Accounts

SCHEDULE II

VALUATION AND QUALIFYING ACCOUNTS

(dollars in thousands)



Accounts Receivable Allowance for Doubtful Accounts	Balance at Beginning of Year		Charged to Expense		Additions/ (Deductions) ⁽¹⁾			Balance at End of Year
2015	$	13,468	$	956	$	(329	)	$	14,095
2014	11,741		301		1,426			13,468
2013	11,172		5,514		(4,945		)	11,741

______________________________


(1)	Primarily accounts receivable written off during the period.

Description Of Business And Significant Accounting Policies (Policy)

12 Months Ended

Dec. 31, 2015

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Description Of Business

Description of Business

Principles Of Consolidation

Principles of Consolidation

Cash And Cash Equivalents

Cash and Cash Equivalents

Cash equivalents consist of highly liquid investments that are readily convertible into cash and have a maturity of three months or less at the date of acquisition.

Investments

Allowance For Doubtful Accounts

Allowance for Doubtful Accounts

Inventories

Inventories primarily include product, material and supplies. Inventories are stated at lower of cost or market. Cost is determined using the first-in, first-out ("FIFO") or average method.

Property, Plant and Equipment

Depreciation is provided by utilizing the straight-line method over the estimated useful lives of the assets as follows:



Classification		Years

Buildings and improvements		25
Plant and equipment		25
Ethylene pipeline		35
Other		3-10

Fair Value Estimates

Impairment Of Long-Lived Assets and Intangible Assets

Impairment of Long-Lived Assets

Impairment of Intangible Assets

Turnaround Costs

Exchanges

Income Taxes

Foreign Currency Translation

Concentration Of Credit Risk

Concentration of Credit Risk

Revenue Recognition

Earnings Per Share

Earnings per Share

Price Risk Management

Environmental Costs

Fair Value Of Financial Instruments

Fair Value of Financial Instruments

Use Of Estimates

Use of Estimates

Other

New Accounting Pronouncements

Recent Accounting Pronouncements

Description Of Business And Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule Of Estimated Useful Lives Of Assets

Depreciation is provided by utilizing the straight-line method over the estimated useful lives of the assets as follows:



Classification		Years

Buildings and improvements		25
Plant and equipment		25
Ethylene pipeline		35
Other		3-10

Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2015

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

Investments in available-for-sale securities at December 31 were classified as follows:



	2015		2014
Current	$	520,144	$	—
Non-current	48,081		15,414
Total available-for-sale securities	$	568,225	$	15,414

Available-for-sale Securities

The cost, gross unrealized gains, gross unrealized losses and fair value of the Company's available-for-sale securities were as follows:



	December 31, 2015
	Cost		Gross Unrealized Gains		Gross Unrealized Losses ⁽¹⁾			Fair Value
Debt securities
Corporate bonds	$	336,665	$	55	$	(1,076	)	$	335,644
U.S. government debt ⁽²⁾	135,226		2		(374		)	134,854
Asset-backed securities	49,759		2		(115		)	49,646
Equity securities	54,371		466		(6,756		)	48,081
Total available-for-sale securities	$	576,021	$	525	$	(8,321	)	$	568,225



	December 31, 2014
	Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Equity securities	$	15,050	$	364	$	—	$	15,414
Total available-for-sale securities	$	15,050	$	364	$	—	$	15,414

______________________________


(1)	All unrealized loss positions were held at a loss for less than 12 months.


(2)	U.S. Treasury obligations, U.S. government agency obligations and U.S government agency mortgage-backed securities.

Schedule of Realized Gain (Loss)



	Year Ended December 31,
	2015			2014			2013
Proceeds from sales and maturities of securities	$	48,900		$	342,045		$	7,770
Gross realized gains	3,830			1,311			20
Gross realized losses	(32		)	(99		)	(39		)

Tabular disclosure of available-for-sale securities which includes, but is not limited to, changes in the cost basis and fair value, fair value and gross unrealized gain (loss), fair values by type of security, contractual maturity and classification, amortized cost basis, contracts to acquire securities to be accounted for as available-for-sale, debt maturities, transfers to trading, change in net unrealized holding gain (loss) net of tax, continuous unrealized loss position fair value, aggregate losses qualitative disclosures, other than temporary impairment (OTTI) losses or other disclosures related to available for sale securities.

Schedule Of Accounts Receivable

Accounts Receivable (Tables)

12 Months Ended

Dec. 31, 2015

Accounts Receivable, Net [Abstract]

Accounts receivable consist of the following at December 31:



	2015			2014
Trade customers	$	438,538		$	525,546
Affiliates	—			437
Allowance for doubtful accounts	(14,095		)	(13,468		)
	424,443			512,515
Federal and state taxes	60,748			8,919
Other	23,341			39,232
Accounts receivable, net	$	508,532		$	560,666

Inventories (Tables)

12 Months Ended

Dec. 31, 2015

Inventory, Net [Abstract]

Schedule Of Inventory

Inventories consist of the following at December 31:



	2015		2014
Finished products	$	253,338	$	300,909
Feedstock, additives and chemicals	106,435		158,635
Materials and supplies	74,287		66,232
Inventories	$	434,060	$	525,776

Property, Plant And Equipment (Tables)

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment, Net [Abstract]

Schedule Of Property, Plant And Equipment

Property, plant and equipment consist of the following at December 31:



	2015			2014
Land	$	33,051		$	21,211
Building and improvements	266,214			244,101
Plant and equipment	3,632,416			3,454,462
Other	241,829			213,707
	4,173,510			3,933,481
Less: Accumulated depreciation	(1,685,255		)	(1,531,331		)
	2,488,255			2,402,150
Construction in progress	515,812			355,407
Property, plant and equipment, net	$	3,004,067		$	2,757,557

Other Assets (Tables)

12 Months Ended

Dec. 31, 2015

Other Assets [Abstract]

Schedule Of Other Assets

Other assets consist of the following at December 31:



	2015							2014							Weighted Average Life
	Cost		Accumulated Amortization			Net		Cost		Accumulated Amortization			Net		Weighted Average Life
Intangible assets:
Licenses and intellectual property	$	79,699	$	(38,643	)	$	41,056	$	82,611	$	(35,732	)	$	46,879	15
Trademarks	39,085		(2,602		)	36,483		42,790		(759		)	42,031		20
Customer relationships	75,249		(22,572		)	52,677		75,249		(17,374		)	57,875		14
Goodwill	62,016		—			62,016		62,016		—			62,016
Other	29,320		(8,148		)	21,172		16,501		(6,871		)	9,630		7
Total intangible assets	285,369		(71,965		)	213,404		279,167		(60,736		)	218,431
Available-for-sale investments	48,081		—			48,081		15,414		—			15,414
Cost-method investments	51,334		—			51,334		57,147		—			57,147
Turnaround costs	111,078		(74,943		)	36,135		107,892		(56,493		)	51,399		5
Debt issuance costs	20,406		(13,286		)	7,120		20,406		(11,282		)	9,124		13
Other	51,682		(20,968		)	30,714		50,571		(18,245		)	32,326		3
Total deferred charges and other assets	282,581		(109,197		)	173,384		251,430		(86,020		)	165,410
Other assets, net	$	567,950	$	(181,162	)	$	386,788	$	530,597	$	(146,756	)	$	383,841

Schedule of Goodwill

he gross carrying amounts of goodwill for the years ended December 31, 2015 and 2014 are as follows:



	Olefins Segment		Vinyls Segment		Total
Balance at December 31, 2013	$	29,990	$	32,026	$	62,016
Goodwill acquired during the year	—		—		—
Balance at December 31, 2014	29,990		32,026		62,016
Changes in goodwill during the year	—		—		—
Balance at December 31, 2015	$	29,990	$	32,026	$	62,016

Accounts and Notes Payable (Tables)

12 Months Ended

Dec. 31, 2015

Accounts and Notes Payable [Abstract]

Accounts and Notes Payable



	2015		2014
Accounts payable	$	229,219	$	261,062
Notes payable to banks	6,110		—
Accounts and notes payable	$	235,329	$	261,062

Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2015

Long-term Debt, Unclassified [Abstract]

Schedule Of Long-Term Debt

Long-term debt consists of the following at December 31:



	2015		2014
3.60% senior notes due 2022	$	249,226	$	249,108
6 ½% senior notes due 2029	100,000		100,000
6 ¾% senior notes due 2032	250,000		250,000
6 ½% senior notes due 2035 (the "6 ½% GO Zone Senior Notes Due 2035")	89,000		89,000
6 ½% senior notes due 2035 (the "6 ½% IKE Zone Senior Notes Due 2035")	65,000		65,000
Loan related to tax-exempt waste disposal revenue bonds due 2027	10,889		10,889
Long-term debt, net	$	764,115	$	763,997

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21538-112644

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644

Accumulated Other Comprehensive Income (Tables)

12 Months Ended

Dec. 31, 2015

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

Changes in accumulated other comprehensive income (loss) by component were as follows:



	Benefits Liability, Net of Tax			Cumulative Foreign Currency Exchange			Net Unrealized Holding Gains on Investments, Net of Tax			Total
Balances at December 31, 2013	$	(6,696	)	$	3,904		$	176		$	(2,616	)
Other comprehensive (loss) income before reclassifications	(17,314		)	(60,128		)	834			(76,608		)
Amounts reclassified from accumulated other comprehensive loss	568			—			(777		)	(209		)
Net other comprehensive (loss) income for the year	(16,746		)	(60,128		)	57			(76,817		)
Balances at December 31, 2014	(23,442		)	(56,224		)	233			(79,433		)
Other comprehensive income (loss) before reclassifications	12,877			(59,466		)	(2,795		)	(49,384		)
Amounts reclassified from accumulated other comprehensive loss	1,958			—			(2,433		)	(475		)
Net other comprehensive income (loss) for the year	14,835			(59,466		)	(5,228		)	(49,859		)
Balances at December 31, 2015	$	(8,607	)	$	(115,690	)	$	(4,995	)	$	(129,292	)

Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]

The following table provides the details of the amounts reclassified from accumulated other comprehensive income (loss) into net income in the consolidated statements of operations:



Details about Accumulated Other Comprehensive Income (Loss) Components	Location of Reclassification (Income (Expense)) in Consolidated Statements of Operations	Year Ended December 31,
		2015			2014			2013
Amortization of pension and other post-retirement items
Prior service costs	(1)	$	—		$	(347	)	$	(381	)
Net loss	(1)	(2,663		)	(577		)	(2,331		)
Settlement benefits	(1)	(355		)	—			—
		(3,018		)	(924		)	(2,712		)
	Provision for income taxes	1,060			356			1,043
		(1,958		)	(568		)	(1,669		)
Net unrealized gains on available-for- sale investments
Realized gain (loss) on available- for-sale investments	Other income (expense), net	3,798			1,212			(19		)
	Provision for income taxes	(1,365		)	(435		)	7
		2,433			777			(12		)
Total reclassifications for the period		$	475		$	209		$	(1,681	)

______________________________


(1)	These accumulated other comprehensive loss components are included in the computation of net periodic benefit cost. For additional information, see Note 11.

Employee Benefits (Tables)

12 Months Ended

Dec. 31, 2015

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Changes in Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status of Plan

Details of the changes in benefit obligations, plan assets and funded status of the Company's pension plans are as follows:



	2015						2014
	U.S. Plans			Non-U.S. Plans			U.S. Plans			Non-U.S. Plans
Change in benefit obligation
Benefit obligation, beginning of year	$	67,010		$	122,701		$	57,946		$	—
Benefit obligation assumed with acquisition	—			—			—			117,970
Service cost	29			1,661			334			602
Interest cost	2,015			2,110			2,322			1,366
Actuarial (gain) loss	(2,330		)	(17,310		)	9,165			15,425
Benefits paid	(4,532		)	(2,139		)	(2,757		)	(898		)
Foreign exchange effects	—			(12,202		)	—			(11,764		)
Benefit obligation, end of year	$	62,192		$	94,821		$	67,010		$	122,701

Change in plan assets
Fair value of plan assets, beginning of year	$	53,415		$	—		$	49,236		$	—
Actual return	(268		)	—			2,953			—
Employer contribution	2,148			2,139			3,983			898
Benefits paid	(4,532		)	(2,139		)	(2,757		)	(898		)
Fair value of plan assets, end of year	$	50,763		$	—		$	53,415		$	—
Funded status, end of year	$	(11,429	)	$	(94,821	)	$	(13,595	)	$	(122,701	)

Schedule of Amounts Recognized in Balance Sheet



	2015						2014
	U.S. Plans			Non-U.S. Plans			U.S. Plans			Non-U.S. Plans
Amounts recognized in the consolidated balance sheet at December 31
Noncurrent liabilities	$	(11,429	)	$	(94,821	)	$	(13,595	)	$	(122,701	)
Net amount recognized	$	(11,429	)	$	(94,821	)	$	(13,595	)	$	(122,701	)

Schedule of Amounts Recognized in Other Comprehensive Income (Loss)



	2015					2014
	U.S. Plans		Non-U.S. Plans			U.S. Plans		Non-U.S. Plans
Amounts recognized in accumulated other comprehensive income
Net loss (gain)	$	14,755	$	(4,919	)	$	15,482	$	15,425
Foreign exchange effects	—		1,986			—		—
Total before tax ⁽¹⁾	$	14,755	$	(2,933	)	$	15,482	$	15,425

Schedule Of Accumulated Benefit Obligations In Excess Of Plan Assets

Pension plans with an accumulated benefit obligation in excess of plan assets at December 31 are as follows:



	2015						2014
Information for pension plans with an accumulated benefit obligation in excess of plan assets	U.S. Plans			Non-U.S. Plans			U.S. Plans			Non-U.S. Plans
Projected benefit obligation	$	(62,192	)	$	(94,821	)	$	(67,010	)	$	(122,701	)
Accumulated benefit obligation	(62,192		)	(93,231		)	(67,010		)	(119,258		)
Fair value of plan assets	50,763			—			53,415			—

Schedule Of Net Benefit Costs And Amounts Recognized In Other Comprehensive Income

The following table provides the components of net periodic benefit costs, other changes in plan assets and benefit obligation recognized in other comprehensive income.



	Year Ended December 31,
	2015						2014					2013
	U.S. Plans			Non-U.S. Plans			U.S. Plans			Non-U.S. Plans		U.S. Plans
Components of net periodic benefit cost
Service cost	$	29		$	1,661		$	334		$	602	$	1,091
Interest cost	2,015			2,110			2,322			1,366		2,047
Expected return on plan assets	(2,960		)	—			(3,140		)	—		(2,854		)
Net amortization	1,270			1,048			571			—		2,255
Settlement benefits	355			—			—			—		—
Net periodic benefit cost	$	709		$	4,819		$	87		$	1,968	$	2,539

Other changes in plan assets and benefit obligation recognized in other comprehensive income (OCI)
Net loss (gain) emerging	$	898		$	(17,310	)	$	9,352		$	15,425	$	(12,468	)
Amortization of net loss	(1,270		)	(1,048		)	(274		)	—		(1,958		)
Amortization of prior service cost	—			—			(297		)	—		(297		)
Settlement benefits	(355		)	—			—			—		—
Total recognized in OCI	$	(727	)	$	(18,358	)	$	8,781		$	15,425	$	(14,723	)
Total net periodic benefit cost and OCI	$	(18	)	$	(13,539	)	$	8,868		$	17,393	$	(12,184	)

Schedule Of Weighted Average Assumptions Used

The weighted-average assumptions used to determine pension plan obligations and net periodic benefit costs for the plans are as follows:



	2015				2014				2013
	U.S. Plans		Non-U.S. Plans		U.S. Plans		Non-U.S. Plans		U.S. Plans
Weighted average assumptions used to determine benefit obligations at December 31
Discount rate	4.0	%	2.4	%	3.5	%	1.9	%	4.5	%
Expected return on plan assets	7.0	%	—	%	7.0	%	—	%	7.0	%
Rate of compensation increase	—	%	2.5	%	—	%	2.5	%	4.0	%
Weighted average assumptions used to determine net periodic benefit costs for years ended December 31
Discount rate	3.5	%	1.9	%	4.5	%	2.6	%	3.3	%
Expected return on plan assets	7.0	%	—	%	7.0	%	—	%	7.0	%
Rate of compensation increase	—	%	2.5	%	—	%	2.5	%	4.0	%

Schedule Of Fair Value Of Pension Plan Assets



	2015				2014
	U.S. Plans				U.S. Plans
	Level 2		Total		Level 2		Total
Bank collective trust funds—Equity securities:
Large-cap index funds ⁽¹⁾	$	18,384	$	18,384	$	19,473	$	19,473
Small-cap index funds ⁽²⁾	4,069		4,069		3,351		3,351
International index funds ⁽³⁾	8,181		8,181		8,474		8,474
Bank collective trust funds—Fixed income:
Bond index funds ⁽⁴⁾	19,624		19,624		21,495		21,495
Short term investment funds	505		505		622		622
	$	50,763	$	50,763	$	53,415	$	53,415

______________________________


(1)	Substantially all of the assets of these funds are invested in large-cap U.S. companies. The remainder of the assets of these funds is invested in cash reserves.


(2)	Substantially all of the assets of these funds are invested in small-cap U.S. companies. The remainder of the assets of these funds is invested in cash reserves.


(3)	Substantially all of the assets of these funds are invested in international companies in developed markets (excluding the United States and Canada). The remainder of the assets of these funds is invested in cash reserves.


(4)	This category represents investment grade bonds of U.S. issuers, including U.S. Treasury notes.

Schedule Of Estimated Future Benefit Payments

The following benefit payments are expected to be paid:



	Pension Benefits		Post- retirement Healthcare
Estimated future benefit payments:
Year 1	$	8,159	$	1,244
Year 2	7,345		1,408
Year 3	7,901		1,409
Year 4	8,461		1,395
Year 5	7,813		1,363
Years 6 to 10	36,897		6,005

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2015

Share-based Compensation [Abstract]

Schedule Of Option Activity And Changes

Option activity and changes during the year ended December 31, 2015 were as follows:



	Options		Weighted Average Exercise Price		Weighted Average Remaining Term (Years)	Aggregate Intrinsic Value
Outstanding at December 31, 2014	1,179,402		$	24.89
Granted	168,369		67.59
Exercised	(32,308	)	32.92
Cancelled	(47,673	)	32.64
Outstanding at December 31, 2015	1,267,790		$	30.07	5.0	$	34,577
Exercisable at December 31, 2015	822,573		$	19.08	4.2	$	29,376

Schedule Of Range Of Exercise Prices For Outstanding Options

For options outstanding at December 31, 2015, the options had the following range of exercise prices:



Range of Prices	Options Outstanding	Weighted Average Remaining Contractual Life (Years)
$7.12 - $9.65	304,200	2.7
$10.26 - $18.05	349,906	2.6
$22.92 - $30.05	191,292	5.7
$40.38 - $52.35	107,562	7.3
$63.98 - $68.18	314,830	8.7

Schedule Of Weighted Average Value And Assumptions For Fair Value Of Options

The table below presents the weighted average value and assumptions used in determining each option's fair value. Volatility was calculated using historical trends of the Company's common stock price.



	Stock Option Grants
	Year Ended December 31,
	2015			2014			2013
Weighted average fair value	$	20.21		$	20.49		$	17.03
Risk-free interest rate	1.7		%	1.6		%	0.9		%
Expected life in years	5			5			5
Expected volatility	34.2		%	35.7		%	44.5		%
Expected dividend yield	0.9		%	0.7		%	0.6		%

Schedule Of Non-Vested Restricted Stock Award Activity And Changes

Non-vested restricted stock awards as of December 31, 2015 and changes during the year ended December 31, 2015 were as follows:



	Number of Shares		Weighted Average Grant Date Fair Value
Non-vested at December 31, 2014	205,056		$	24.52
Vested	(124,380	)	30.17
Forfeited	(15,820	)	15.81
Non-vested at December 31, 2015	64,856		$	15.81

Derivative Commodity Instruments (Tables)

12 Months Ended

Dec. 31, 2015

Derivative Instruments and Hedges, Assets [Abstract]

Fair Values Of Derivative Instruments In Consolidated Balance Sheets

The fair values of derivative instruments in the Company's consolidated balance sheets were as follows:



	Asset Derivatives
	Balance Sheet Location	Fair Value as of December 31,
	Balance Sheet Location	2015		2014
Not designated as hedging instruments
Commodity forward contracts	Accounts receivable, net	$	3,465	$	3,145
Commodity forward contracts	Deferred charges and other assets, net	2,088		—
Total asset derivatives		$	5,553	$	3,145

	Liability Derivatives
	Balance Sheet Location	Fair Value as of December 31,
	Balance Sheet Location	2015		2014
Not designated as hedging instruments
Commodity forward contracts	Accrued liabilities	$	9,325	$	6,549
Commodity forward contracts	Other liabilities	12,437		3,559
Total liability derivatives		$	21,762	$	10,108

Impact Of Derivative Instruments Designated As Fair Value Hedges

Impact Of Derivative Instruments Not Designated As Fair Value Hedges

The impact of derivative instruments that have not been designated as hedges on the Company's consolidated statements of operations were as follows:



Derivatives Not Designated as Hedging Instruments	Location of Gain (Loss) Recognized in Income on Derivative	Year Ended December 31,
Derivatives Not Designated as Hedging Instruments	Location of Gain (Loss) Recognized in Income on Derivative	2015			2014			2013
Commodity forward contracts	Gross profit	$	(11,395	)	$	(9,678	)	$	5,438

Offsetting of Derivative Assets



	Derivative Assets as of December 31,
	2015		2014
Derivative assets subject to enforceable master netting arrangements	$	—	$	2,333
Derivative assets not subject to enforceable master netting arrangements	462		111
Total derivative assets	$	462	$	2,444



	December 31, 2015							December 31, 2014
Offsetting of Derivative Assets	Gross Amounts of Recognized Assets		Gross Amounts Offset in the Consolidated Balance Sheet			Net Amounts of Assets Presented in the Consolidated Balance Sheet		Gross Amounts of Recognized Assets		Gross Amounts Offset in the Consolidated Balance Sheet			Net Amounts of Assets Presented in the Consolidated Balance Sheet
Commodity forward contracts	$	5,091	$	(5,091	)	$	—	$	3,034	$	(701	)	$	2,333



	December 31, 2015						December 31, 2014
Derivative Assets by Counterparty	Net Amounts of Assets Presented in the Consolidated Balance Sheet		Gross Amounts Not Offset in the Consolidated Balance Sheet		Net Amount		Net Amounts of Assets Presented in the Consolidated Balance Sheet		Gross Amounts Not Offset in the Consolidated Balance Sheet		Net Amount
Counterparty A	$	—	$	—	$	—	$	2,333	$	—	$	2,333
Total	$	—	$	—	$	—	$	2,333	$	—	$	2,333

Offsetting of Derivative Liabilities



	Derivative Liabilities as of December 31,
	2015		2014
Derivative liabilities subject to enforceable master netting arrangements	$	5,803	$	1,490
Derivative liabilities not subject to enforceable master netting arrangements	10,868		7,917
Total derivative liabilities	$	16,671	$	9,407



	December 31, 2015							December 31, 2014
Offsetting of Derivative Liabilities	Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Consolidated Balance Sheet			Net Amounts of Liabilities Presented in the Consolidated Balance Sheet		Gross Amounts of Recognized Liabilities		Gross Amounts Offset in the Consolidated Balance Sheet			Net Amounts of Liabilities Presented in the Consolidated Balance Sheet
Commodity forward contracts	$	10,894	$	(5,091	)	$	5,803	$	2,191	$	(701	)	$	1,490



	December 31, 2015						December 31, 2014
Derivative Liabilities by Counterparty	Net Amounts of Liabilities Presented in the Consolidated Balance Sheet		Gross Amounts Not Offset in the Consolidated Balance Sheet		Net Amount		Net Amounts of Liabilities Presented in the Consolidated Balance Sheet		Gross Amounts Not Offset in the Consolidated Balance Sheet		Net Amount
Counterparty A	$	5,564	$	—	$	5,564	$	1,490	$	—	$	1,490
Counterparty B	239		—		239		—		—		—
Total	$	5,803	$	—	$	5,803	$	1,490	$	—	$	1,490

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2015

Fair Value Disclosures [Abstract]

Schedule Of Assets And Liabilities On A Recurring Basis

The following tables summarize, by level within the fair value hierarchy, the Company's assets and liabilities at December 31 that were accounted for at fair value on a recurring basis:



	2015
	Level 1			Level 2			Total
Derivative instruments
Risk management assets—Commodity forward contracts	$	5,553		$	—		$	5,553
Risk management liabilities—Commodity forward contracts	(11,648		)	(10,114		)	(21,762		)
Marketable securities
Available-for-sale securities	48,081			520,144			568,225

	2014
	Level 1			Level 2			Total
Derivative instruments
Risk management assets—Commodity forward contracts	$	3,143		$	2		$	3,145
Risk management liabilities—Commodity forward contracts	—			(10,108		)	(10,108		)
Marketable securities
Available-for-sale securities	15,414			—			15,414

Schedule Of Carrying And Fair Values Of Long-Term Debt

The carrying and fair values of the Company's long-term debt at December 31, 2015 and 2014 are summarized in the table below. The Company's long-term debt instruments are publicly-traded. A market approach, based upon quotes from financial reporting services, is used to measure the fair value of the Company's long-term debt. Because the Company's long-term debt instruments may not be actively traded, the inputs used to measure the fair value of the Company's long-term debt are classified as Level 2 inputs within the fair value hierarchy.



	2015				2014
	Carrying Value		Fair Value		Carrying Value		Fair Value
3.60% senior notes due 2022	$	249,226	$	244,828	$	249,108	$	248,630
6 ½% senior notes due 2029	100,000		117,153		100,000		116,384
6 ¾% senior notes due 2032	250,000		268,490		250,000		285,545
6 ½% GO Zone Senior Notes Due 2035	89,000		106,491		89,000		106,504
6 ½% IKE Zone Senior Notes Due 2035	65,000		76,741		65,000		77,784
Loan related to tax-exempt waste disposal revenue bonds due 2027	10,889		10,889		10,889		10,889

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Components Of Income (Loss) Before Income Taxes

The components of income (loss) before income taxes are as follows:



	Year Ended December 31,
	2015		2014			2013
Domestic	$	880,044	$	1,102,101		$	944,378
Foreign	83,397		(18,183		)	(2,206		)
	$	963,441	$	1,083,918		$	942,172

Schedule Of The Provision For (Benefit From) Income Taxes

The Company's provision for (benefit from) income taxes consists of the following:



	Year Ended December 31,
	2015		2014			2013
Current
Federal	$	225,617	$	300,610		$	215,903
State	23,966		37,351			22,249
Foreign	9,029		1,974			(137		)
	258,612		339,935			238,015
Deferred
Federal	29,820		40,950			94,471
State	2,807		22,714			(556		)
Foreign	7,157		(4,697		)	(183		)
	39,784		58,967			93,732
Total provision	$	298,396	$	398,902		$	331,747

Reconciliation Of Taxes Computed At The Statutory Rate To Income Tax Expense

A reconciliation of taxes computed at the statutory rate to the Company's income tax expense is as follows:



	Year Ended December 31,
	2015			2014			2013
Provision for federal income tax, at statutory rate	$	337,204		$	379,371		$	329,760
State income tax provision, net of federal income tax effect	17,403			40,012			14,364
Foreign income tax rate differential	(13,002		)	3,640			519
Manufacturing deduction	(24,185		)	(24,465		)	(16,275		)
Contingent tax liability	—			(1,626		)	(404		)
Noncontrolling interests	(6,662		)	(2,255		)	—
Other, net	(12,362		)	4,225			3,783
	$	298,396		$	398,902		$	331,747

Schedule Of Deferred Tax Assets And Liabilities

The tax effects of the principal temporary differences between financial reporting and income tax reporting at December 31 are as follows:



	2015			2014
Net operating loss carryforward	$	17,679		$	18,200
Credit carryforward	746			694
Accruals	62,204			62,845
Allowance for doubtful accounts	4,617			1,998
Inventories	8,663			11,437
Other	7,747			7,660
Deferred taxes assets—total	101,656			102,834
Property, plant and equipment	(423,381		)	(398,683		)
Turnaround costs	(1,467		)	(2,289		)
Basis difference—consolidated partnerships	(200,627		)	(194,480		)
Deferred tax liabilities—total	(625,475		)	(595,452		)
Valuation allowance	(16,345		)	(11,011		)
Total net deferred tax liabilities	$	(540,164	)	$	(503,629	)

Balance sheet classifications
Current deferred tax asset	$	35,439		$	32,437
Noncurrent deferred tax liability	(575,603		)	(536,066		)
Total net deferred tax liabilities	$	(540,164	)	$	(503,629	)

Schedule Of Changes In Gross Unrecognized Tax Benefits

The gross unrecognized tax benefits at December 31 are as follows:



	2015		2014
Beginning balance	$	—	$	2,501
Reductions due to statutes of limitations expiring	—		(2,501		)
Ending balance	$	—	$	—

Earnings Per Share (Tables)

12 Months Ended

Dec. 31, 2015

Earnings Per Share [Abstract]

Schedule Of Net Income Attributable To Common Stockholders



	Year Ended December 31,
	2015			2014			2013
Net income attributable to Westlake Chemical Corporation	$	646,010		$	678,523		$	610,425
Less:
Net income attributable to participating securities	(2,825		)	(1,502		)	(2,562		)
Net income attributable to common shareholders	$	643,185		$	677,021		$	607,863

Reconciliation Of Denominator For Basic And Diluted Earnings (Loss) Per Share

The following table reconciles the denominator for the basic and diluted earnings per share computations shown in the consolidated statements of operations:



	Year Ended December 31,
	2015		2014		2013
Weighted average common shares—basic ⁽¹⁾	131,823,707		133,111,230		133,224,256
Plus incremental shares from:
Assumed exercise of options ⁽¹⁾	478,105		532,184		554,994
Weighted average common shares—diluted ⁽¹⁾	132,301,812		133,643,414		133,779,250

Earnings per common share attributable to Westlake Chemical Corporation: ⁽¹⁾
Basic	$	4.88	$	5.09	$	4.57
Diluted	$	4.86	$	5.07	$	4.55

Supplemental Information (Tables)

12 Months Ended

Dec. 31, 2015

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule Of Other Income, Net



	Year Ended December 31,
	2015			2014			2013
Interest income	$	6,034		$	3,468		$	3,086
Dividend income	3,559			532			—
Foreign exchange currency gains (losses), net ⁽¹⁾	1,828			(7,382		)	(1,375		)
Income from equity method investments	6,242			5,883			4,914
Impairment of equity method investments	(4,925		)	(6,747		)	—
Gain on acquisition and related expenses, net	20,430			—			—
Gains (losses) from sales of securities, net	3,798			1,212			(19		)
Other	1,304			313			184
Other income (expense), net	$	38,270		$	(2,721	)	$	6,790

Schedule of Cash Flow Information

h Flow Information



	Year Ended December 31,
	2015		2014		2013
Cash paid for:
Interest paid, net of interest capitalized	$	31,946	$	35,336	$	16,426
Income taxes paid	314,186		314,745		251,599

Supplemental Noncash Investing Activities

In conjunction with the acquisitions discussed in Note 21, liabilities assumed consist of the following:



	Year Ended December 31,
	2015			2014
Fair value of assets acquired	$	44,013		$	961,823
Fair value of investment before business combination, net of preexisting balances	(10,352		)	—
Noncontrolling interest acquired	(1,597		)	—
Cash paid	(5,518		)	(736,224		)
Liabilities assumed	$	26,546		$	225,599

Westlake Chemical Partners LP (Tables)

12 Months Ended

Dec. 31, 2015

Reconciliation Of Proceeds From Initial Public Offering

The following table is a reconciliation of proceeds from the initial public offering:



Total proceeds from the initial public offering	$	310,500
Less: Offering Costs	(24,412		)
Net proceeds from the initial public offering	286,088
Less: Cash retained by OpCo	(55,419		)
Net proceeds distributed to the Company from the initial public offering	$	230,669

Acquisitions (Tables)

12 Months Ended

Dec. 31, 2015

Suzhou Huasu Plastics Company Ltd [Member]

Business Acquisition [Line Items]

Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]



Fair value of consideration transferred—cash	$	5,518
Preexisting balances between the Company and Huasu, net	(8,538		)
Fair value of the Company's investment in Huasu before the business combination ⁽¹⁾	18,890
Fair value of the noncontrolling interest in Huasu ⁽¹⁾	1,597
	$	17,467

Preliminary allocation of consideration transferred to net assets acquired:
Cash	$	21,300
Working capital, excluding inventory and cash ⁽²⁾	(5,461		)
Inventories	17,717
Property, plant and equipment	19,786
Other assets	7,760
Notes payable to banks	(21,085		)
Total identifiable net assets	40,017
Bargain purchase gain on acquisition	$	22,550

______________________________


(1)	The fair values of the Company's 59.3% equity interest and the noncontrolling interest were estimated using internally developed, unobservable inputs (Level 3 inputs in the fair value hierarchy of fair value accounting) based on a cost approach.


(2)	The fair value of accounts receivable acquired is $2,515, with the gross contractual amount being $3,006. The Company expects $491 to be uncollectible.

Vinnolit [Member]

Business Acquisition [Line Items]

Business Acquisition, Pro Forma Information



	Pro Forma Year Ended December 31,
	2014		2013
Net sales	$	5,152,806	$	4,976,998

Net income	$	737,913	$	666,202
Net income attributable to noncontrolling interests	6,493		—
Net income attributable to Westlake Chemical Corporation	$	731,420	$	666,202
Earnings per common share attributable to Westlake Chemical Corporation:
Basic	$	5.48	$	4.98
Diluted	$	5.46	$	4.96

Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]



Fair value of consideration transferred:
Cash paid to Sellers	$	309,619
Cash deposited in escrow ⁽¹⁾	13,390
Retirement of long-term debt as of July 31, 2014, on behalf of the Sellers ⁽²⁾	413,215
Total purchase consideration	$	736,224

Allocation of consideration transferred to net assets acquired:
Cash	$	125,137
Working capital, excluding inventory and cash ⁽³⁾	15,373
Inventories ⁽⁴⁾	114,961
Property, plant and equipment	469,484
Investments	51,552
Other assets ⁽⁵⁾	76,828
Intangible assets:
Trademarks and trade name (weighted average life of 20 years)	40,170
Developed technologies (weighted average life of 20 years)	31,600
Other intangibles (weighted average life of 9.4 years)	1,422
Deferred income tax asset—current	7,909
Deferred income tax asset—non-current	27,387
Pension obligation	(117,970		)
Other long-term liabilities	(10,723		)
Power purchase agreement liability ⁽⁶⁾	(10,826		)
Deferred income tax liability—current	(6,845		)
Deferred income tax liability—non-current	(79,235		)
Total identifiable net assets	736,224
Goodwill ⁽⁷⁾	—
Consideration transferred	$	736,224

______________________________


(1)	None of the cash held in escrow is considered contingent consideration as it is expected to be released to the Sellers pending the Sellers' satisfaction of general representations and warranties made in connection with the execution of the purchase agreement.


(2)	Vinnolit's long-term debt paid on behalf of the Sellers was not legally assumed by Westlake in the acquisition and the retirement was a condition of the consummation of the purchase agreement. Therefore, the retirement has been included in the total purchase consideration.


(3)	The fair value of accounts receivable acquired is $181,890, with the gross contractual amount being $183,833. The Company expects $1,943 to be uncollectable.


(4)	An adjustment of approximately $16,900 was recorded to reflect Vinnolit's inventories at fair value and increased cost of sales by the same amount for the year ended December 31, 2014.


(5)	Included in other assets was a loan acquired that was repaid prior to December 31, 2014.


(6)	A liability arising from the unfavorable forward purchase contracts for the purchase of power was recognized at fair value. This liability will be amortized over a period of approximately three years, being the weighted-average life of the forward purchase contracts.


(7)	As the fair value of the net assets acquired equals consideration paid, no goodwill was recorded.

Commitments And Contingencies (Tables)

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

Future Minimum Lease Commitments

Several of the leases provide for renewal terms and, in certain leases, purchase options. At December 31, 2015, future minimum lease commitments for operating lease obligations and capital lease obligations were as follows:



	Operating Leases		Capital Leases
2016	$	43,200	$	245
2017	42,293		245
2018	35,119		245
2019	29,164		245
2020	24,124		245
Thereafter	582,327		779
Total minimum lease payments	$	756,227	$	2,004
Less: Imputed interest costs			(519		)
Present value of net minimum lease payments			$	1,485

Segment And Geographic Information (Tables)

12 Months Ended

Dec. 31, 2015

Segment Reporting [Abstract]

Segment Reporting Information



	Year Ended December 31,
	2015			2014			2013
Net external sales
Olefins
Polyethylene	$	1,650,964		$	1,922,535		$	1,750,292
Styrene, feedstock and other	609,149			801,155			803,377
Total olefins	2,260,113			2,723,690			2,553,669
Vinyls
PVC, caustic soda and other	1,718,359			1,203,332			800,658
Building products	484,864			488,328			405,157
Total vinyls	2,203,223			1,691,660			1,205,815
	$	4,463,336		$	4,415,350		$	3,759,484

Intersegment sales
Olefins	$	106,861		$	146,539		$	320,909
Vinyls	1,493			1,385			1,502
	$	108,354		$	147,924		$	322,411

Income (loss) from operations
Olefins	$	747,436		$	1,013,825		$	833,249
Vinyls	254,452			142,740			154,684
Corporate and other	(42,061		)	(32,574		)	(34,469		)
	$	959,827		$	1,123,991		$	953,464

Depreciation and amortization
Olefins	$	110,684		$	106,244		$	102,938
Vinyls	134,546			101,666			54,371
Corporate and other	527			576			499
	$	245,757		$	208,486		$	157,808

Other income (expense), net
Olefins	$	4,656		$	6,102		$	7,410
Vinyls	8,540			2,680			(1,858		)
Corporate and other	25,074			(11,503		)	1,238
	$	38,270		$	(2,721	)	$	6,790

Provision for (benefit from) income taxes
Olefins	$	242,516		$	354,159		$	288,214
Vinyls	64,456			52,249			48,296
Corporate and other	(8,576		)	(7,506		)	(4,763		)
	$	298,396		$	398,902		$	331,747

Capital expenditures
Olefins	$	304,873		$	188,729		$	145,542
Vinyls	176,582			237,992			531,939
Corporate and other	9,971			4,383			1,741
	$	491,426		$	431,104		$	679,222

Total Assets



	December 31, 2015		December 31, 2014
Total assets
Olefins	$	1,869,888	$	1,785,895
Vinyls	2,638,833		2,618,646
Corporate and other	1,066,531		809,449
	$	5,575,252	$	5,213,990

Reconciliation Of Total Segment Income From Operations To Consolidated Income Before Income Taxes

A reconciliation of total segment income from operations to consolidated income before income taxes is as follows:



	Year Ended December 31,
	2015			2014			2013
Income from operations for reportable segments	$	959,827		$	1,123,991		$	953,464
Interest expense	(34,656		)	(37,352		)	(18,082		)
Other income (expense), net	38,270			(2,721		)	6,790
Income before income taxes	$	963,441		$	1,083,918		$	942,172

Geographic Information For Sales To External Customers And Long-Lived Assets



	Year Ended December 31,
	2015		2014		2013
Sales to external customers ⁽¹⁾
United States	$	3,133,395	$	3,596,091	$	3,404,378
Foreign
Germany	394,459		198,921		3,942
Canada	195,790		217,567		214,162
Switzerland	106,750		89,214		54,637
Italy	90,237		36,823		55
France	58,727		27,521		8,207
Other	483,978		249,213		74,103
	$	4,463,336	$	4,415,350	$	3,759,484



	December 31, 2015		December 31, 2014
Long-lived assets
United States	$	2,588,366	$	2,319,572
Foreign
Germany	379,262		417,702
Other	36,439		20,283
	$	3,004,067	$	2,757,557

______________________________


(1)	Revenues are attributed to countries based on location of customer.

Guarantor Disclosures (Tables)

12 Months Ended

Dec. 31, 2015

Guarantor Disclosures [Abstract]

Condensed Consolidating Financial Information Balance Sheet

Condensed Consolidating Financial Information as of December 31, 2015



	Westlake Chemical Corporation		100% Owned Guarantor Subsidiaries		OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries		Eliminations			Consolidated
Balance Sheet
Current assets
Cash and cash equivalents	$	303,131	$	6,828	$	163,430	$	189,136	$	—		$	662,525
Marketable securities	520,144		—		—		—		—			520,144
Accounts receivable, net	10,943		2,183,276		51,582		113,321		(1,850,590		)	508,532
Inventories	—		326,588		3,879		103,593		—			434,060
Prepaid expenses and other current assets	2,201		12,166		267		2,734		(2,879		)	14,489
Deferred income taxes	702		32,787		—		1,950		—			35,439
Total current assets	837,121		2,561,645		219,158		410,734		(1,853,469		)	2,175,189
Property, plant and equipment, net	—		1,567,897		1,020,469		415,701		—			3,004,067
Equity investments	4,991,167		1,207,679		—		469,915		(6,659,553		)	9,208
Other assets, net	17,896		450,428		44,157		129,539		(255,232		)	386,788
Total assets	$	5,846,184	$	5,787,649	$	1,283,784	$	1,425,889	$	(8,768,254	)	$	5,575,252
Current liabilities
Accounts and notes payable	$	1,817,963	$	121,820	$	33,901	$	87,510	$	(1,825,865	)	$	235,329
Accrued liabilities	9,117		195,785		21,873		88,142		(27,604		)	287,313
Total current liabilities	1,827,080		317,605		55,774		175,652		(1,853,469		)	522,642
Long-term debt	753,226		10,889		248,665		—		(248,665		)	764,115
Deferred income taxes	—		532,837		1,392		47,941		(6,567		)	575,603
Other liabilities	—		49,334		—		101,627		—			150,961
Total liabilities	2,580,306		910,665		305,831		325,220		(2,108,701		)	2,013,321
Total Westlake Chemical Corporation stockholders' equity	3,265,878		4,876,984		977,953		804,616		(6,659,553		)	3,265,878
Noncontrolling interests	—		—		—		296,053		—			296,053
Total equity	3,265,878		4,876,984		977,953		1,100,669		(6,659,553		)	3,561,931
Total liabilities and equity	$	5,846,184	$	5,787,649	$	1,283,784	$	1,425,889	$	(8,768,254	)	$	5,575,252

Condensed Consolidating Financial Information as of December 31, 2014



	Westlake Chemical Corporation		100% Owned Guarantor Subsidiaries		OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries		Eliminations			Consolidated
Balance Sheet
Current assets
Cash and cash equivalents	$	655,947	$	3,057	$	131,545	$	90,052	$	—		$	880,601
Accounts receivable, net	8,451		1,454,709		56,049		135,133		(1,093,676		)	560,666
Inventories	—		414,975		6,634		104,167		—			525,776
Prepaid expenses and other current assets	172		9,485		212		1,938		—			11,807
Deferred income taxes	409		29,832		—		2,196		—			32,437
Total current assets	664,979		1,912,058		194,440		333,486		(1,093,676		)	2,011,287
Property, plant and equipment, net	—		1,477,515		842,057		437,985		—			2,757,557
Equity investments	4,033,378		1,237,080		—		352,550		(5,561,703		)	61,305
Other assets, net	30,543		387,325		57,733		141,948		(233,708		)	383,841
Total assets	$	4,728,900	$	5,013,978	$	1,094,230	$	1,265,969	$	(6,889,087	)	$	5,213,990
Current liabilities
Accounts payable	$	1,055,527	$	160,834	$	17,680	$	95,856	$	(1,068,835	)	$	261,062
Accrued liabilities	8,754		203,608		11,225		77,372		(24,841		)	276,118
Total current liabilities	1,064,281		364,442		28,905		173,228		(1,093,676		)	537,180
Long-term debt	753,108		10,889		227,638		—		(227,638		)	763,997
Deferred income taxes	—		497,919		1,848		42,369		(6,070		)	536,066
Other liabilities	—		43,452		—		131,407		—			174,859
Total liabilities	1,817,389		916,702		258,391		347,004		(1,327,384		)	2,012,102
Total Westlake Chemical Corporation stockholders' equity	2,911,511		4,097,276		835,839		628,588		(5,561,703		)	2,911,511
Noncontrolling interests	—		—		—		290,377		—			290,377
Total equity	2,911,511		4,097,276		835,839		918,965		(5,561,703		)	3,201,888
Total liabilities and equity	$	4,728,900	$	5,013,978	$	1,094,230	$	1,265,969	$	(6,889,087	)	$	5,213,990

Schedule of Guarantor Obligations

ondensed Consolidating Financial Information as of December 31, 2015



	Westlake Chemical Corporation		100% Owned Guarantor Subsidiaries		OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries		Eliminations			Consolidated
Balance Sheet
Current assets
Cash and cash equivalents	$	303,131	$	6,828	$	163,430	$	189,136	$	—		$	662,525
Marketable securities	520,144		—		—		—		—			520,144
Accounts receivable, net	10,943		2,183,276		51,582		113,321		(1,850,590		)	508,532
Inventories	—		326,588		3,879		103,593		—			434,060
Prepaid expenses and other current assets	2,201		12,166		267		2,734		(2,879		)	14,489
Deferred income taxes	702		32,787		—		1,950		—			35,439
Total current assets	837,121		2,561,645		219,158		410,734		(1,853,469		)	2,175,189
Property, plant and equipment, net	—		1,567,897		1,020,469		415,701		—			3,004,067
Equity investments	4,991,167		1,207,679		—		469,915		(6,659,553		)	9,208
Other assets, net	17,896		450,428		44,157		129,539		(255,232		)	386,788
Total assets	$	5,846,184	$	5,787,649	$	1,283,784	$	1,425,889	$	(8,768,254	)	$	5,575,252
Current liabilities
Accounts and notes payable	$	1,817,963	$	121,820	$	33,901	$	87,510	$	(1,825,865	)	$	235,329
Accrued liabilities	9,117		195,785		21,873		88,142		(27,604		)	287,313
Total current liabilities	1,827,080		317,605		55,774		175,652		(1,853,469		)	522,642
Long-term debt	753,226		10,889		248,665		—		(248,665		)	764,115
Deferred income taxes	—		532,837		1,392		47,941		(6,567		)	575,603
Other liabilities	—		49,334		—		101,627		—			150,961
Total liabilities	2,580,306		910,665		305,831		325,220		(2,108,701		)	2,013,321
Total Westlake Chemical Corporation stockholders' equity	3,265,878		4,876,984		977,953		804,616		(6,659,553		)	3,265,878
Noncontrolling interests	—		—		—		296,053		—			296,053
Total equity	3,265,878		4,876,984		977,953		1,100,669		(6,659,553		)	3,561,931
Total liabilities and equity	$	5,846,184	$	5,787,649	$	1,283,784	$	1,425,889	$	(8,768,254	)	$	5,575,252

Condensed Consolidating Financial Information as of December 31, 2014



	Westlake Chemical Corporation		100% Owned Guarantor Subsidiaries		OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries		Eliminations			Consolidated
Balance Sheet
Current assets
Cash and cash equivalents	$	655,947	$	3,057	$	131,545	$	90,052	$	—		$	880,601
Accounts receivable, net	8,451		1,454,709		56,049		135,133		(1,093,676		)	560,666
Inventories	—		414,975		6,634		104,167		—			525,776
Prepaid expenses and other current assets	172		9,485		212		1,938		—			11,807
Deferred income taxes	409		29,832		—		2,196		—			32,437
Total current assets	664,979		1,912,058		194,440		333,486		(1,093,676		)	2,011,287
Property, plant and equipment, net	—		1,477,515		842,057		437,985		—			2,757,557
Equity investments	4,033,378		1,237,080		—		352,550		(5,561,703		)	61,305
Other assets, net	30,543		387,325		57,733		141,948		(233,708		)	383,841
Total assets	$	4,728,900	$	5,013,978	$	1,094,230	$	1,265,969	$	(6,889,087	)	$	5,213,990
Current liabilities
Accounts payable	$	1,055,527	$	160,834	$	17,680	$	95,856	$	(1,068,835	)	$	261,062
Accrued liabilities	8,754		203,608		11,225		77,372		(24,841		)	276,118
Total current liabilities	1,064,281		364,442		28,905		173,228		(1,093,676		)	537,180
Long-term debt	753,108		10,889		227,638		—		(227,638		)	763,997
Deferred income taxes	—		497,919		1,848		42,369		(6,070		)	536,066
Other liabilities	—		43,452		—		131,407		—			174,859
Total liabilities	1,817,389		916,702		258,391		347,004		(1,327,384		)	2,012,102
Total Westlake Chemical Corporation stockholders' equity	2,911,511		4,097,276		835,839		628,588		(5,561,703		)	2,911,511
Noncontrolling interests	—		—		—		290,377		—			290,377
Total equity	2,911,511		4,097,276		835,839		918,965		(5,561,703		)	3,201,888
Total liabilities and equity	$	4,728,900	$	5,013,978	$	1,094,230	$	1,265,969	$	(6,889,087	)	$	5,213,990

Condensed Consolidating Financial Information for the Year Ended December 31, 2015



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Operations
Net sales	$	—		$	3,660,393		$	1,007,221		$	1,039,165		$	(1,243,443	)	$	4,463,336
Cost of sales	—			2,944,420			624,339			933,007			(1,223,621		)	3,278,145
Gross profit	—			715,973			382,882			106,158			(19,822		)	1,185,191
Selling, general and administrative expenses	2,478			167,431			20,138			55,139			(19,822		)	225,364
(Loss) income from operations	(2,478		)	548,542			362,744			51,019			—			959,827
Interest expense	(42,197		)	(10		)	(2,691		)	(521		)	10,763			(34,656		)
Other income (expense), net	19,614			1,033			(63		)	28,449			(10,763		)	38,270
(Loss) income before income taxes	(25,061		)	549,565			359,990			78,947			—			963,441
(Benefit from) provision for income taxes	(7,237		)	288,329			672			16,632			—			298,396
Equity in net income of subsidiaries	663,834			314,026			—			45,292			(1,023,152		)	—
Net income	646,010			575,262			359,318			107,607			(1,023,152		)	665,045
Net income attributable to noncontrolling interests	—			—			—			19,035			—			19,035
Net income attributable to Westlake Chemical Corporation	$	646,010		$	575,262		$	359,318		$	88,572		$	(1,023,152	)	$	646,010
Comprehensive income attributable to Westlake Chemical Corporation	$	596,151		$	572,731		$	359,318		$	42,143		$	(974,192	)	$	596,151

Condensed Consolidating Financial Information for the Year Ended December 31, 2014



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Operations
Net sales	$	—		$	3,727,361		$	1,749,700		$	475,401		$	(1,537,112	)	$	4,415,350
Cost of sales	—			3,162,246			1,003,888			447,676			(1,515,810		)	3,098,000
Gross profit	—			565,115			745,812			27,725			(21,302		)	1,317,350
Selling, general and administrative expenses	2,082			144,987			26,870			40,722			(21,302		)	193,359
(Loss) income from operations	(2,082		)	420,128			718,942			(12,997		)	—			1,123,991
Interest expense	(39,763		)	(10		)	(10,499		)	(492		)	13,412			(37,352		)
Other income (expense), net	21,001			(4,921		)	3,151			(8,540		)	(13,412		)	(2,721		)
(Loss) income before income taxes	(20,844		)	415,197			711,594			(22,029		)	—			1,083,918
Provision for (benefit from) income taxes	248			202,501			199,388			(3,235		)	—			398,902
Equity in net income of subsidiaries	699,615			496,244			—			15,962			(1,211,821		)	—
Net income (loss)	678,523			708,940			512,206			(2,832		)	(1,211,821		)	685,016
Net income attributable to noncontrolling interests	—			—			—			6,493			—			6,493
Net income (loss) attributable to Westlake Chemical Corporation	$	678,523		$	708,940		$	512,206		$	(9,325	)	$	(1,211,821	)	$	678,523
Comprehensive income (loss) attributable to Westlake Chemical Corporation	$	601,706		$	703,148		$	512,206		$	(80,407	)	$	(1,134,947	)	$	601,706

Condensed Consolidating Financial Information for the Year Ended December 31, 2013



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Operations
Net sales	$	—		$	3,195,406		$	2,127,747		$	48,016		$	(1,611,685	)	$	3,759,484
Cost of sales	—			2,971,258			1,255,140			43,333			(1,611,685		)	2,658,046
Gross profit	—			224,148			872,607			4,683			—			1,101,438
Selling, general and administrative expenses	2,128			114,211			25,451			6,184			—			147,974
(Loss) income from operations	(2,128		)	109,937			847,156			(1,501		)	—			953,464
Interest expense	(18,030		)	(52		)	(8,032		)	—			8,032			(18,082		)
Other income (expense), net	11,798			(2,438		)	7,701			(2,239		)	(8,032		)	6,790
(Loss) income before income taxes	(8,360		)	107,447			846,825			(3,740		)	—			942,172
(Benefit from) provision for income taxes	(2,031		)	34,340			300,279			(841		)	—			331,747
Equity in net income of subsidiaries	616,754			546,546			—			—			(1,163,300		)	—
Net income (loss) attributable to Westlake Chemical Corporation	$	610,425		$	619,653		$	546,546		$	(2,899	)	$	(1,163,300	)	$	610,425
Comprehensive income (loss) attributable to Westlake Chemical Corporation	$	618,649		$	629,308		$	546,546		$	(4,506	)	$	(1,171,348	)	$	618,649

Condensed Consolidating Financial Information for the Year Ended December 31, 2015



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Cash Flows
Cash flows from operating activities
Net income	$	646,010		$	575,262		$	359,318		$	107,607		$	(1,023,152	)	$	665,045
Adjustments to reconcile net income to net cash (used for) provided by operating activities
Depreciation and amortization	2,004			124,897			81,210			39,650			—			247,761
Deferred income taxes	(285		)	33,369			(456		)	7,156			—			39,784
Net changes in working capital and other	(660,777		)	(368,494		)	19,175			113,190			1,023,152			126,246
Net cash (used for) provided by operating activities	(13,048		)	365,034			459,247			267,603			—			1,078,836
Cash flows from investing activities
Acquisition of business, net of cash acquired	—			—			—			15,782			—			15,782
Additions to property, plant and equipment	—			(215,405		)	(231,185		)	(44,836		)	—			(491,426		)
Proceeds from disposition of assets	—			18			—			31			—			49
Proceeds from disposition of equity method investment	—			27,865			—			—			—			27,865
Proceeds from sales and maturities of securities	48,900			—			—			—			—			48,900
Purchase of securities	(556,211		)	(48,887		)	—			—			—			(605,098		)
Settlements of derivative instruments	—			(2,248		)	—			—			—			(2,248		)
Net cash used for investing activities	(507,311		)	(238,657		)	(231,185		)	(29,023		)	—			(1,006,176		)
Cash flows from financing activities
Intercompany financing	418,844			(585,007		)	156,368			9,795			—			—
Intercompany financing—OpCo	—			135,341			(135,341		)	—			—			—
Dividends paid	(91,551		)	—			—			—			—			(91,551		)
Distributions paid	—			327,060			(352,545		)	10,629			—			(14,856		)
Purchase of limited partner interests	—			—			135,341			(135,341		)	—			—
Proceeds from exercise of stock options	1,063			—			—			—			—			1,063
Proceeds from issuance of notes payable	—			—			—			52,960			—			52,960
Repayment of notes payable	—			—			—			(73,615		)	—			(73,615		)
Repurchase of common stock for treasury	(162,459		)	—			—			—			—			(162,459		)
Windfall tax benefits from share-based payment arrangements	1,646			—			—			—			—			1,646
Net cash provided by (used for) financing activities	$	167,543		$	(122,606	)	$	(196,177	)	$	(135,572	)	$	—		$	(286,812	)



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries		OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries			Eliminations		Consolidated
Effect of exchange rate changes on cash and cash equivalents	$	—		$	—	$	—	$	(3,924	)	$	—	$	(3,924	)
Net (decrease) increase in cash and cash equivalents	(352,816		)	3,771		31,885		99,084			—		(218,076		)
Cash and cash equivalents at beginning of the year	655,947			3,057		131,545		90,052			—		880,601
Cash and cash equivalents at end of the year	$	303,131		$	6,828	$	163,430	$	189,136		$	—	$	662,525

Condensed Consolidating Financial Information for the Year Ended December 31, 2014



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Cash Flows
Cash flows from operating activities
Net income (loss)	$	678,523		$	708,940		$	512,206		$	(2,832	)	$	(1,211,821	)	$	685,016
Adjustments to reconcile net income (loss) to net cash (used for) provided by operating activities
Depreciation and amortization	1,673			111,389			77,611			19,486			—			210,159
Deferred income taxes	(288		)	55,344			8,608			(4,697		)	—			58,967
Net changes in working capital and other	(706,043		)	(1,077,982		)	4,879			645,559			1,211,821			78,234
Net cash (used for) provided by operating activities	(26,135		)	(202,309		)	603,304			657,516			—			1,032,376
Cash flows from investing activities
Acquisition of business, net of cash acquired	—			—			—			(611,087		)	—			(611,087		)
Additions to property, plant and equipment	—			(209,111		)	(202,823		)	(19,170		)	—			(431,104		)
Proceeds from disposition of assets	—			180			—			1			—			181
Proceeds from repayment of loan acquired	—			—			—			45,923			—			45,923
Proceeds from sales and maturities of securities	342,045			—			—			—			—			342,045
Purchase of securities	(117,332		)	—			—			—			—			(117,332		)
Settlements of derivative instruments	—			(1,698		)	(133		)	—			—			(1,831		)
Net cash provided by (used for) investing activities	224,713			(210,629		)	(202,956		)	(584,333		)	—			(773,205		)
Cash flows from financing activities
Intercompany financing	155,665			(244,122		)	102,702			(14,245		)	—			—
Net distributions prior to Westlake Partners initial public offering	—			448,101			(448,101		)	—			—			—
Capitalized debt issuance costs	(1,186		)	—			—			—			—			(1,186		)
Dividends paid	(77,656		)	151,729			(151,729		)	—			—			(77,656		)
Distributions paid	—			54,060			(57,763		)	1,499			—			(2,204		)
Net proceeds from issuance of Westlake Partners common units	—			—			—			286,088			—			286,088
Purchase of limited partner interests	—			—			286,088			(286,088		)	—			—
Proceeds from exercise of stock options	5,524			—			—			—			—			5,524
Repurchase of common stock for treasury	(52,630		)	—			—			—			—			(52,630		)
Windfall tax benefits from share-based payment arrangements	6,704			—			—			—			—			6,704
Net cash provided by (used for) financing activities	$	36,421		$	409,768		$	(268,803	)	$	(12,746	)	$	—		$	164,640



	Westlake Chemical Corporation		100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries			Eliminations		Consolidated
Effect of exchange rate changes on cash and cash equivalents	$	—	$	—		$	—	$	(4,511	)	$	—	$	(4,511	)
Net increase (decrease) in cash and cash equivalents	234,999		(3,170		)	131,545		55,926			—		419,300
Cash and cash equivalents at beginning of the year	420,948		6,227			—		34,126			—		461,301
Cash and cash equivalents at end of the year	$	655,947	$	3,057		$	131,545	$	90,052		$	—	$	880,601

Condensed Consolidating Financial Information for the Year Ended December 31, 2013



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Cash Flows
Cash flows from operating activities
Net income (loss)	$	610,425		$	619,653		$	546,546		$	(2,899	)	$	(1,163,300	)	$	610,425
Adjustments to reconcile net income (loss) to net cash (used for) provided by operating activities
Depreciation and amortization	1,459			81,897			73,463			2,448			—			159,267
Deferred income taxes	74			56,787			37,054			(183		)	—			93,732
Net changes in working capital and other	(622,194		)	(607,033		)	(54,554		)	9,786			1,163,300			(110,695		)
Net cash (used for) provided by operating activities	(10,236		)	151,304			602,509			9,152			—			752,729
Cash flows from investing activities
Acquisition of business	—			(178,309		)	—			—			—			(178,309		)
Additions to equity investments	—			(23,338		)	—			—			—			(23,338		)
Additions to property, plant and equipment	—			(453,538		)	(223,130		)	(2,554		)	—			(679,222		)
Construction of assets pending sale-leaseback	—			(136		)	—			—			—			(136		)
Proceeds from disposition of assets	—			75			—			76			—			151
Proceeds from repayment of loan to affiliate	—			—			—			167			—			167
Proceeds from sales and maturities of securities	252,519			—			—			—			—			252,519
Purchase of securities	(367,150		)	—			—			—			—			(367,150		)
Settlements of derivative instruments	—			—			(6,920		)	—			—			(6,920		)
Net cash used for investing activities	(114,631		)	(655,246		)	(230,050		)	(2,311		)	—			(1,002,238		)
Cash flows from financing activities
Intercompany financing	(128,798		)	(100,330		)	231,067			(1,939		)	—			—
Net distributions prior to Westlake Partners initial public offering	—			603,526			(603,526		)	—			—			—
Dividends paid	(55,236		)	—			—			—			—			(55,236		)
Proceeds from exercise of stock options	3,437			—			—			—			—			3,437
Repurchase of common stock for treasury	(32,918		)	—			—			—			—			(32,918		)
Windfall tax benefits from share-based payment arrangements	5,449			—			—			—			—			5,449
Net cash (used for) provided by financing activities	$	(208,066	)	$	503,196		$	(372,459	)	$	(1,939	)	$	—		$	(79,268	)



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries		Eliminations		Consolidated
Net (decrease) increase in cash and cash equivalents	$	(332,933	)	$	(746	)	$	—	$	4,902	$	—	$	(328,777	)
Cash and cash equivalents at beginning of the year	753,881			6,973			—		29,224		—		790,078
Cash and cash equivalents at end of the year	$	420,948		$	6,227		$	—	$	34,126	$	—	$	461,301

Condensed Consolidating Financial Information Statement Of Operations

Condensed Consolidating Financial Information for the Year Ended December 31, 2015



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Operations
Net sales	$	—		$	3,660,393		$	1,007,221		$	1,039,165		$	(1,243,443	)	$	4,463,336
Cost of sales	—			2,944,420			624,339			933,007			(1,223,621		)	3,278,145
Gross profit	—			715,973			382,882			106,158			(19,822		)	1,185,191
Selling, general and administrative expenses	2,478			167,431			20,138			55,139			(19,822		)	225,364
(Loss) income from operations	(2,478		)	548,542			362,744			51,019			—			959,827
Interest expense	(42,197		)	(10		)	(2,691		)	(521		)	10,763			(34,656		)
Other income (expense), net	19,614			1,033			(63		)	28,449			(10,763		)	38,270
(Loss) income before income taxes	(25,061		)	549,565			359,990			78,947			—			963,441
(Benefit from) provision for income taxes	(7,237		)	288,329			672			16,632			—			298,396
Equity in net income of subsidiaries	663,834			314,026			—			45,292			(1,023,152		)	—
Net income	646,010			575,262			359,318			107,607			(1,023,152		)	665,045
Net income attributable to noncontrolling interests	—			—			—			19,035			—			19,035
Net income attributable to Westlake Chemical Corporation	$	646,010		$	575,262		$	359,318		$	88,572		$	(1,023,152	)	$	646,010
Comprehensive income attributable to Westlake Chemical Corporation	$	596,151		$	572,731		$	359,318		$	42,143		$	(974,192	)	$	596,151

Condensed Consolidating Financial Information for the Year Ended December 31, 2014



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Operations
Net sales	$	—		$	3,727,361		$	1,749,700		$	475,401		$	(1,537,112	)	$	4,415,350
Cost of sales	—			3,162,246			1,003,888			447,676			(1,515,810		)	3,098,000
Gross profit	—			565,115			745,812			27,725			(21,302		)	1,317,350
Selling, general and administrative expenses	2,082			144,987			26,870			40,722			(21,302		)	193,359
(Loss) income from operations	(2,082		)	420,128			718,942			(12,997		)	—			1,123,991
Interest expense	(39,763		)	(10		)	(10,499		)	(492		)	13,412			(37,352		)
Other income (expense), net	21,001			(4,921		)	3,151			(8,540		)	(13,412		)	(2,721		)
(Loss) income before income taxes	(20,844		)	415,197			711,594			(22,029		)	—			1,083,918
Provision for (benefit from) income taxes	248			202,501			199,388			(3,235		)	—			398,902
Equity in net income of subsidiaries	699,615			496,244			—			15,962			(1,211,821		)	—
Net income (loss)	678,523			708,940			512,206			(2,832		)	(1,211,821		)	685,016
Net income attributable to noncontrolling interests	—			—			—			6,493			—			6,493
Net income (loss) attributable to Westlake Chemical Corporation	$	678,523		$	708,940		$	512,206		$	(9,325	)	$	(1,211,821	)	$	678,523
Comprehensive income (loss) attributable to Westlake Chemical Corporation	$	601,706		$	703,148		$	512,206		$	(80,407	)	$	(1,134,947	)	$	601,706

Condensed Consolidating Financial Information for the Year Ended December 31, 2013



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Operations
Net sales	$	—		$	3,195,406		$	2,127,747		$	48,016		$	(1,611,685	)	$	3,759,484
Cost of sales	—			2,971,258			1,255,140			43,333			(1,611,685		)	2,658,046
Gross profit	—			224,148			872,607			4,683			—			1,101,438
Selling, general and administrative expenses	2,128			114,211			25,451			6,184			—			147,974
(Loss) income from operations	(2,128		)	109,937			847,156			(1,501		)	—			953,464
Interest expense	(18,030		)	(52		)	(8,032		)	—			8,032			(18,082		)
Other income (expense), net	11,798			(2,438		)	7,701			(2,239		)	(8,032		)	6,790
(Loss) income before income taxes	(8,360		)	107,447			846,825			(3,740		)	—			942,172
(Benefit from) provision for income taxes	(2,031		)	34,340			300,279			(841		)	—			331,747
Equity in net income of subsidiaries	616,754			546,546			—			—			(1,163,300		)	—
Net income (loss) attributable to Westlake Chemical Corporation	$	610,425		$	619,653		$	546,546		$	(2,899	)	$	(1,163,300	)	$	610,425
Comprehensive income (loss) attributable to Westlake Chemical Corporation	$	618,649		$	629,308		$	546,546		$	(4,506	)	$	(1,171,348	)	$	618,649

Condensed Consolidating Financial Information Statement Of Cash Flows

Condensed Consolidating Financial Information for the Year Ended December 31, 2015



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Cash Flows
Cash flows from operating activities
Net income	$	646,010		$	575,262		$	359,318		$	107,607		$	(1,023,152	)	$	665,045
Adjustments to reconcile net income to net cash (used for) provided by operating activities
Depreciation and amortization	2,004			124,897			81,210			39,650			—			247,761
Deferred income taxes	(285		)	33,369			(456		)	7,156			—			39,784
Net changes in working capital and other	(660,777		)	(368,494		)	19,175			113,190			1,023,152			126,246
Net cash (used for) provided by operating activities	(13,048		)	365,034			459,247			267,603			—			1,078,836
Cash flows from investing activities
Acquisition of business, net of cash acquired	—			—			—			15,782			—			15,782
Additions to property, plant and equipment	—			(215,405		)	(231,185		)	(44,836		)	—			(491,426		)
Proceeds from disposition of assets	—			18			—			31			—			49
Proceeds from disposition of equity method investment	—			27,865			—			—			—			27,865
Proceeds from sales and maturities of securities	48,900			—			—			—			—			48,900
Purchase of securities	(556,211		)	(48,887		)	—			—			—			(605,098		)
Settlements of derivative instruments	—			(2,248		)	—			—			—			(2,248		)
Net cash used for investing activities	(507,311		)	(238,657		)	(231,185		)	(29,023		)	—			(1,006,176		)
Cash flows from financing activities
Intercompany financing	418,844			(585,007		)	156,368			9,795			—			—
Intercompany financing—OpCo	—			135,341			(135,341		)	—			—			—
Dividends paid	(91,551		)	—			—			—			—			(91,551		)
Distributions paid	—			327,060			(352,545		)	10,629			—			(14,856		)
Purchase of limited partner interests	—			—			135,341			(135,341		)	—			—
Proceeds from exercise of stock options	1,063			—			—			—			—			1,063
Proceeds from issuance of notes payable	—			—			—			52,960			—			52,960
Repayment of notes payable	—			—			—			(73,615		)	—			(73,615		)
Repurchase of common stock for treasury	(162,459		)	—			—			—			—			(162,459		)
Windfall tax benefits from share-based payment arrangements	1,646			—			—			—			—			1,646
Net cash provided by (used for) financing activities	$	167,543		$	(122,606	)	$	(196,177	)	$	(135,572	)	$	—		$	(286,812	)



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries		OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries			Eliminations		Consolidated
Effect of exchange rate changes on cash and cash equivalents	$	—		$	—	$	—	$	(3,924	)	$	—	$	(3,924	)
Net (decrease) increase in cash and cash equivalents	(352,816		)	3,771		31,885		99,084			—		(218,076		)
Cash and cash equivalents at beginning of the year	655,947			3,057		131,545		90,052			—		880,601
Cash and cash equivalents at end of the year	$	303,131		$	6,828	$	163,430	$	189,136		$	—	$	662,525

Condensed Consolidating Financial Information for the Year Ended December 31, 2014



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Cash Flows
Cash flows from operating activities
Net income (loss)	$	678,523		$	708,940		$	512,206		$	(2,832	)	$	(1,211,821	)	$	685,016
Adjustments to reconcile net income (loss) to net cash (used for) provided by operating activities
Depreciation and amortization	1,673			111,389			77,611			19,486			—			210,159
Deferred income taxes	(288		)	55,344			8,608			(4,697		)	—			58,967
Net changes in working capital and other	(706,043		)	(1,077,982		)	4,879			645,559			1,211,821			78,234
Net cash (used for) provided by operating activities	(26,135		)	(202,309		)	603,304			657,516			—			1,032,376
Cash flows from investing activities
Acquisition of business, net of cash acquired	—			—			—			(611,087		)	—			(611,087		)
Additions to property, plant and equipment	—			(209,111		)	(202,823		)	(19,170		)	—			(431,104		)
Proceeds from disposition of assets	—			180			—			1			—			181
Proceeds from repayment of loan acquired	—			—			—			45,923			—			45,923
Proceeds from sales and maturities of securities	342,045			—			—			—			—			342,045
Purchase of securities	(117,332		)	—			—			—			—			(117,332		)
Settlements of derivative instruments	—			(1,698		)	(133		)	—			—			(1,831		)
Net cash provided by (used for) investing activities	224,713			(210,629		)	(202,956		)	(584,333		)	—			(773,205		)
Cash flows from financing activities
Intercompany financing	155,665			(244,122		)	102,702			(14,245		)	—			—
Net distributions prior to Westlake Partners initial public offering	—			448,101			(448,101		)	—			—			—
Capitalized debt issuance costs	(1,186		)	—			—			—			—			(1,186		)
Dividends paid	(77,656		)	151,729			(151,729		)	—			—			(77,656		)
Distributions paid	—			54,060			(57,763		)	1,499			—			(2,204		)
Net proceeds from issuance of Westlake Partners common units	—			—			—			286,088			—			286,088
Purchase of limited partner interests	—			—			286,088			(286,088		)	—			—
Proceeds from exercise of stock options	5,524			—			—			—			—			5,524
Repurchase of common stock for treasury	(52,630		)	—			—			—			—			(52,630		)
Windfall tax benefits from share-based payment arrangements	6,704			—			—			—			—			6,704
Net cash provided by (used for) financing activities	$	36,421		$	409,768		$	(268,803	)	$	(12,746	)	$	—		$	164,640



	Westlake Chemical Corporation		100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries			Eliminations		Consolidated
Effect of exchange rate changes on cash and cash equivalents	$	—	$	—		$	—	$	(4,511	)	$	—	$	(4,511	)
Net increase (decrease) in cash and cash equivalents	234,999		(3,170		)	131,545		55,926			—		419,300
Cash and cash equivalents at beginning of the year	420,948		6,227			—		34,126			—		461,301
Cash and cash equivalents at end of the year	$	655,947	$	3,057		$	131,545	$	90,052		$	—	$	880,601

Condensed Consolidating Financial Information for the Year Ended December 31, 2013



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)			Non-Guarantor Subsidiaries			Eliminations			Consolidated
Statement of Cash Flows
Cash flows from operating activities
Net income (loss)	$	610,425		$	619,653		$	546,546		$	(2,899	)	$	(1,163,300	)	$	610,425
Adjustments to reconcile net income (loss) to net cash (used for) provided by operating activities
Depreciation and amortization	1,459			81,897			73,463			2,448			—			159,267
Deferred income taxes	74			56,787			37,054			(183		)	—			93,732
Net changes in working capital and other	(622,194		)	(607,033		)	(54,554		)	9,786			1,163,300			(110,695		)
Net cash (used for) provided by operating activities	(10,236		)	151,304			602,509			9,152			—			752,729
Cash flows from investing activities
Acquisition of business	—			(178,309		)	—			—			—			(178,309		)
Additions to equity investments	—			(23,338		)	—			—			—			(23,338		)
Additions to property, plant and equipment	—			(453,538		)	(223,130		)	(2,554		)	—			(679,222		)
Construction of assets pending sale-leaseback	—			(136		)	—			—			—			(136		)
Proceeds from disposition of assets	—			75			—			76			—			151
Proceeds from repayment of loan to affiliate	—			—			—			167			—			167
Proceeds from sales and maturities of securities	252,519			—			—			—			—			252,519
Purchase of securities	(367,150		)	—			—			—			—			(367,150		)
Settlements of derivative instruments	—			—			(6,920		)	—			—			(6,920		)
Net cash used for investing activities	(114,631		)	(655,246		)	(230,050		)	(2,311		)	—			(1,002,238		)
Cash flows from financing activities
Intercompany financing	(128,798		)	(100,330		)	231,067			(1,939		)	—			—
Net distributions prior to Westlake Partners initial public offering	—			603,526			(603,526		)	—			—			—
Dividends paid	(55,236		)	—			—			—			—			(55,236		)
Proceeds from exercise of stock options	3,437			—			—			—			—			3,437
Repurchase of common stock for treasury	(32,918		)	—			—			—			—			(32,918		)
Windfall tax benefits from share-based payment arrangements	5,449			—			—			—			—			5,449
Net cash (used for) provided by financing activities	$	(208,066	)	$	503,196		$	(372,459	)	$	(1,939	)	$	—		$	(79,268	)



	Westlake Chemical Corporation			100% Owned Guarantor Subsidiaries			OpCo (Less Than 100% Owned Guarantor Subsidiary)		Non-Guarantor Subsidiaries		Eliminations		Consolidated
Net (decrease) increase in cash and cash equivalents	$	(332,933	)	$	(746	)	$	—	$	4,902	$	—	$	(328,777	)
Cash and cash equivalents at beginning of the year	753,881			6,973			—		29,224		—		790,078
Cash and cash equivalents at end of the year	$	420,948		$	6,227		$	—	$	34,126	$	—	$	461,301

Quarterly Financial Information (Tables)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Summary Of Quarterly Financial Information



	Three Months Ended
	March 31, 2015		June 30, 2015		September 30, 2015		December 31, 2015
Net sales	$	1,103,531	$	1,185,002	$	1,188,037	$	986,766
Gross profit	284,546		353,181		311,276		236,188
Income from operations	229,280		295,374		254,028		181,145
Net income attributable to Westlake Chemical Corporation	146,342		205,095		183,604		110,969
Earnings per common share attributable to Westlake Chemical Corporation: ⁽¹⁾
Basic	$	1.10	$	1.55	$	1.39	$	0.85
Diluted	$	1.10	$	1.54	$	1.39	$	0.84

	Three Months Ended
	March 31, 2014		June 30, 2014		September 30, 2014		December 31, 2014
Net sales	$	1,027,676	$	998,576	$	1,253,227	$	1,135,871
Gross profit	287,010		305,971		361,520		362,849
Income from operations	248,055		266,788		306,761		302,387
Net income attributable to Westlake Chemical Corporation	158,032		169,443		167,757		183,291
Earnings per common share attributable to Westlake Chemical Corporation: ⁽¹⁾
Basic	$	1.18	$	1.27	$	1.26	$	1.38
Diluted	$	1.18	$	1.26	$	1.25	$	1.37

______________________________


(1)	Basic and diluted earnings per common share ("EPS") for each quarter is computed using the weighted average shares outstanding during that quarter, while EPS for the year is computed using the weighted average shares outstanding for the year. As a result, the sum of the EPS for each of the four quarters may not equal the EPS for the year.

Description Of Business And Significant Accounting Policies (Narrative) (Details) $ in Thousands		12 Months Ended
	Aug. 04, 2014 shares	Dec. 31, 2015 USD ($) plant	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Undistributed earnings included in retained earnings		$ 0
Capitalized interest		10,449	$ 7,059	$ 25,932
Goodwill		$ 62,016	$ 62,016	$ 62,016
Amortization period, minimum (in years)		3 years
Amortization period, maximum (in years)		6 years
Other assets amortization period, minimum (in years)		1 year
Other assets amortization period, maximum (in years)		30 years
Subsidiaries [Member] \| Limited Partner [Member] \| IPO [Member] \| Westlake Chemical Partners LP [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of units sold in public offering \| shares	12,937,500
Limited partner interest	10.60%
Westlake Chemical OpCo LP [Member] \| Limited Partner [Member] \| IPO [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Limited partner interest	89.40%	86.70%
Westlake Chemical OpCo LP [Member] \| Subsidiaries [Member] \| Louisiana
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of production facilities \| plant		2
Westlake Chemical OpCo LP [Member] \| Subsidiaries [Member] \| Kentucky
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of production facilities \| plant		1
Westlake Chemical OpCo LP [Member] \| Subsidiaries [Member] \| Limited Partner [Member] \| IPO [Member] \| Subsidiary of Common Parent [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Limited partner interest	10.60%	13.30%

Description Of Business And Significant Accounting Policies (Schedule Of Estimated Useful Lives Of Assets) (Details)	12 Months Ended
	Dec. 31, 2015
Buildings And Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, minimum (in years)	25 years
Plant And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, minimum (in years)	25 years
Ethylene Pipeline [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, minimum (in years)	35 years
Minimum [Member] \| Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, minimum (in years)	3 years
Maximum [Member] \| Other [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life, minimum (in years)	10 years

Financial Instruments Cash Equivalents (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Held-to-maturity Securities [Member]
Cash Equivalents [Line Items]
Cash equivalents	$ 221,918	$ 509,811

Financial Instruments Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Current	$ 520,144	$ 0
Non-current	48,081	15,414
Total Available-for-sale Securities	$ 568,225	$ 15,414

Investments in debt and equity securities which are categorized neither as held-to-maturity nor trading and which are intended to be sold or mature more than one year from the balance sheet date or operating cycle, if longer. Such securities are reported at fair value; unrealized gains (losses) related to Available-for-sale Securities are excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain (loss) of an Available-for-sale security that is designated as being hedged in a fair value hedge is recognized in earnings during the period of the hedge, as are other than temporary declines in fair value below the cost basis for investments in equity securities and debt securities that an entity intends to sell or it is more likely than not that it will be required to sell before the recovery of its amortized cost basis. Other than temporary declines in fair value below the cost basis for debt securities categorized as Available-for-sale that an entity does not intend to sell and for which it is not more likely than not that the entity will be required to sell before the recovery of its amortized cost basis are bifurcated into credit losses and losses related to all other factors. Other than temporary declines in fair value below cost basis related to credit losses are recognized in earnings, and losses related to all other factors are recognized in other comprehensive income.

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Financial Instruments Available-for-sale Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Cost	$ 576,021	$ 15,050
Gross Unrealized Gains	525	364
Gross Unrealized Losses	(8,321)	0
Fair Value	568,225	15,414
Net unrealized (losses) gains on AFS securities	(4,995)	233
Income tax (benefit) expense on net unrealized (losses) gains on AFS securities	(2,801)	131
Proceeds from sales and maturities of securities	48,900	342,045	$ 7,770
Gross realized gains	3,830	1,311	20
Gross realized losses	(32)	(99)	$ (39)
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	54,371	15,050
Gross Unrealized Gains	466	364
Gross Unrealized Losses	(6,756)	0
Fair Value	48,081	$ 15,414
Corporate Bond Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	336,665
Gross Unrealized Gains	55
Gross Unrealized Losses	(1,076)
Fair Value	$ 335,644
Corporate Bond Securities [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity term of investments	3 months
Corporate Bond Securities [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity term of investments	5 years
US Treasury and Government [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	$ 135,226
Gross Unrealized Gains	2
Gross Unrealized Losses	(374)
Fair Value	$ 134,854
US Treasury and Government [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity term of investments	1 month
US Treasury and Government [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity term of investments	3 years
Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost	$ 49,759
Gross Unrealized Gains	2
Gross Unrealized Losses	(115)
Fair Value	$ 49,646
Asset-backed Securities [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity term of investments	1 year
Asset-backed Securities [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity term of investments	6 years
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity term of investments	5 years

Accounts Receivable (Schedule Of Accounts Receivable) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accounts Receivable, Net [Abstract]
Trade customers	$ 438,538	$ 525,546
Affiliates	0	437
Allowance for doubtful accounts	(14,095)	(13,468)
Receivables from trade customers and affiliates, net	424,443	512,515
Federal and state taxes	60,748	8,919
Other	23,341	39,232
Accounts receivable, net	$ 508,532	$ 560,666

Inventories (Schedule Of Inventory) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Inventory, Net [Abstract]
Finished products	$ 253,338	$ 300,909
Feedstock, additives, and chemicals	106,435	158,635
Materials and supplies	74,287	66,232
Inventories	$ 434,060	$ 525,776

Property, Plant And Equipment (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Depreciation expense on property, plant and equipment	$ 209,271	$ 174,173	$ 129,222

Property, Plant And Equipment (Schedule Of Property, Plant And Equipment) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment, Net [Abstract]
Land	$ 33,051	$ 21,211
Building and improvements	266,214	244,101
Plant and equipment	3,632,416	3,454,462
Other	241,829	213,707
Property, plant and equipment, gross	4,173,510	3,933,481
Less: Accumulated depreciation	(1,685,255)	(1,531,331)
Property, plant and equipment, net, before construction in progress	2,488,255	2,402,150
Construction in progress	515,812	355,407
Property, plant and equipment, net	$ 3,004,067	$ 2,757,557

Other Assets (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
Other Assets (Narrative) (Details) - USD ($) $ in Thousands	Oct. 31, 2015	Apr. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Assets [Line Items]
Amortization expense of other assets			$ 38,490	$ 35,986	$ 30,045
Future amortization expense, 2016			15,189
Future amortization expense, 2017			13,219
Future amortization expense, 2018			13,195
Future amortization expense, 2019			11,446
Future amortization expense, 2020			9,950
Impairment since goodwill was initially recorded			$ 0
Olefins [Member]
Other Assets [Line Items]
Number of years forecasted to test for impairment of goodwill	9 years
Rate used to discount future cash flows for goodwill impairment test	8.80%
Percentage future cash flows of segment could decrease by and not be impaired	10.00%
Vinyls [Member]
Other Assets [Line Items]
Rate used to discount future cash flows for goodwill impairment test		11.50%
Percentage future cash flows of segment could decrease by and not be impaired		10.00%
Minimum [Member]
Other Assets [Line Items]
Discounted cash flow projections period	2016	2015
Maximum [Member]
Other Assets [Line Items]
Discounted cash flow projections period	2024	2023,

Other Assets (Schedule Of Other Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill, Cost	$ 62,016	$ 62,016
Goodwill, Net	62,016	62,016	$ 62,016
Total intangible assets	285,369	279,167
Intangible assets, Accumulated Amortization	(71,965)	(60,736)
Intangible assets, net	213,404	218,431
Available-for-sale investments	48,081	15,414
Cost-method investments	51,334	57,147
Turnaround costs	111,078	107,892
Turnaround costs, Accumulated Amortization	(74,943)	(56,493)
Turnaround costs, Net	36,135	51,399
Debt issuance costs, Cost	20,406	20,406
Debt issuance costs, Accumulated Amortization	(13,286)	(11,282)
Debt issuance costs, Net	7,120	9,124
Other, Costs	51,682	50,571
Other, Accumulated Amortization	(20,968)	(18,245)
Other, Net	30,714	32,326
Other assets, Cost	567,950	530,597
Other assets, Accumulated Amortization	(181,162)	(146,756)
Other assets, net	(386,788)	(383,841)
Total deferred charges and other assets, Cost	282,581	251,430
Total deferred charges and other assets, Accumulated Amortization	(109,197)	(86,020)
Total deferred charges and other assets, Net	$ 173,384	165,410
Turnaround Costs [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Weighted Average Life	5 years
Debt Issuance Costs [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Weighted Average Life	13 years
Other, Net [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Weighted Average Life	3 years
Licenses and intellectual property [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets, Cost	$ 79,699	82,611
Intangible assets, Accumulated Amortization	(38,643)	(35,732)
Intangible assets, Net	$ 41,056	46,879
Weighted Average Life	15 years
Trademarks [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets, Cost	$ 39,085	42,790
Intangible assets, Accumulated Amortization	(2,602)	(759)
Intangible assets, Net	$ 36,483	42,031
Weighted Average Life	20 years
Customer relationships [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets, Cost	$ 75,249	75,249
Intangible assets, Accumulated Amortization	(22,572)	(17,374)
Intangible assets, Net	$ 52,677	57,875
Weighted Average Life	14 years
Other [Member]
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets, Cost	$ 29,320	16,501
Intangible assets, Accumulated Amortization	(8,148)	(6,871)
Intangible assets, Net	$ 21,172	$ 9,630
Weighted Average Life	7 years

Other Assets (Goodwill) (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
Other Assets (Goodwill) (Details) - USD ($) $ in Thousands	Oct. 31, 2015	Apr. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Impairment since goodwill was initially recorded			$ 0
Goodwill			62,016	$ 62,016	$ 62,016
Goodwill, Other Changes			0
Goodwill, Acquired During Period				0
Olefins [Member]
Goodwill [Line Items]
Goodwill			29,990	29,990	29,990
Goodwill, Other Changes			0
Goodwill, Acquired During Period				0
Vinyls [Member]
Goodwill [Line Items]
Goodwill			32,026	32,026	$ 32,026
Goodwill, Other Changes			$ 0
Goodwill, Acquired During Period				$ 0
Minimum [Member]
Goodwill [Line Items]
Discounted cash flow projections period	2016	2015
Maximum [Member]
Goodwill [Line Items]
Discounted cash flow projections period	2024	2023,

Accounts and Notes Payable (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accounts and Notes Payable [Abstract]
Accounts payable	$ 229,219	$ 261,062
Notes payable to banks	6,110	0
Accounts and notes payable	$ 235,329	$ 261,062

Long-Term Debt (Schedule Of Long-Term Debt) (Details) - USD ($)		1 Months Ended	12 Months Ended
	Jul. 17, 2012	Dec. 31, 1997	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2012
Debt Instrument [Line Items]
Long-term debt			$ 764,115,000	$ 763,997,000
Stated interest rate			6.50%
3.60% Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Senior notes			$ 249,226,000	$ 249,108,000
Stated interest rate	3.60%		3.60%	3.60%	3.60%
Maturity	2022		2022
GO Zone 6 1/2% Senior Notes Due 2029 [Member]
Debt Instrument [Line Items]
Senior notes			$ 100,000,000	$ 100,000,000
Stated interest rate			6.50%	6.50%
Maturity			2029
GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Senior notes			$ 250,000,000	$ 250,000,000
Stated interest rate			6.75%	6.75%
Maturity			2032
GO Zone 6 1/2% Tax-Exempt Revenue Bonds Due 2035 [Member]
Debt Instrument [Line Items]
Senior notes			$ 89,000,000	$ 89,000,000
Stated interest rate			6.50%	6.50%
Maturity			2035
Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member]
Debt Instrument [Line Items]
Senior notes			$ 65,000,000	$ 65,000,000
Stated interest rate			6.50%	6.50%
Maturity			2035
Waste Disposal Revenue Bonds Due 2027 [Member]
Debt Instrument [Line Items]
Non-current loan payable			$ 10,889,000	$ 10,889,000
Maturity		December 2027	2027
Minimum [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Covenant Terms, Acquisitions Restrictions, Borrowing Availability Threshold, Percent Of Commitments, Scenario One			15.00%
Line of Credit Facility, Covenant Terms, Distributions Restrictions, Borrowing Availability Threshold, Scenario Two			$ 50,000,000
Maximum [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Covenant Terms, Distributions Restrictions, Borrowing Availability Threshold, Scenario Two			$ 60,000,000

Long-Term Debt (Senior Secured Revolving Credit Facility) (Details)	12 Months Ended
	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Increase in credit facility borrowings	$ 25,000,000
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 400,000,000
Amounts drawn under the facility limited to accounts receivable, percentage	85.00%
Amounts drawn under the facility limited to eligible inventory, percentage	70.00%
Amounts drawn under the facility limited to lesser of eligible inventory orderly liquidation, percentage	85.00%
Amounts drawn under the facility limited to cash held in an account with the agent	100.00%
Sub-limit for letters of credit facility	$ 400,000,000
Long-term Line of Credit	$ 0
Percentage of commitment on borrowing availability	0.25%
Letters of credit outstanding	$ 30,098,000
Remaining borrowing capacity	$ 320,843,000
Borrowing availability compliance requirements for credit facility	20.00%
Borrowing availability compliance requirements for credit facility	$ 80,000,000
Senior Secured Revolving Credit Facility [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate, Maximum, Provided Company Rated Investment Grade	1.50%
Senior Secured Revolving Credit Facility [Member] \| Minimum [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Percentage added to basis to find interest rate	1.25%
Senior Secured Revolving Credit Facility [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Percentage added to basis to find interest rate	0.00%
Senior Secured Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Increase in credit facility borrowings	$ 200,000,000
Covenant terms, specified distributions permissible	$ 82,700,000
Covenant Terms, specified distributions permissible, annual increase, percentage	5.00%
Senior Secured Revolving Credit Facility [Member] \| Maximum [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Percentage added to basis to find interest rate	1.75%
Senior Secured Revolving Credit Facility [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Percentage added to basis to find interest rate	0.50%

Long-Term Debt (Senior Notes Due 2022) (Details) - USD ($) $ in Thousands		12 Months Ended
	Jul. 17, 2012	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2012
Debt Instrument [Line Items]
Stated interest rate		6.50%
3.60% Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued	$ 250,000
Stated interest rate	3.60%	3.60%	3.60%	3.60%
Maturity	2022	2022
Senior notes, original discount issue	$ 1,183
Senior notes, repurchase price as percentage of principal amount upon change of control and below investment grade rating event		101.00%
Senior notes, maximum number of days from change of control for below investment grade rating event		60 days
Senior notes, minimum debt amount guaranteed by subsidiaries		$ 5,000
3.60% Senior Notes Due 2022 [Member] \| Prior to April Fifteenth Twenty Twenty Two
Debt Instrument [Line Items]
Senior notes, redemption price as percentage of principal amount		100.00%
3.60% Senior Notes Due 2022 [Member] \| On or After April Fifteenth Twenty Twenty Two
Debt Instrument [Line Items]
Senior notes, redemption price as percentage of principal amount		100.00%

Long-Term Debt (GO Zone Act Senior Notes Due 2035) (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Dec. 31, 2010	Jul. 31, 2010	Dec. 31, 2015	Dec. 31, 2014	Dec. 02, 2010	Jul. 02, 2010
Debt Instrument [Line Items]
Stated interest rate			6.50%
Minimum Debt Amount Guaranteed By Subsidiaries			$ 5,000
GO Zone 6 1/2% Tax-Exempt Revenue Bonds Due 2035 [Member]
Debt Instrument [Line Items]
Stated interest rate			6.50%	6.50%
GO Zone 6 1/2% Tax-Exempt Revenue Bonds Due 2035 [Member] \| Redeemed Prior To November 1, 2020 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called			100.00%
GO Zone 6 1/2% Tax-Exempt Revenue Bonds Due 2035 [Member] \| Redeemed On Or After November 1, 2020 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called			100.00%
Gulf Opportunity Zone Act Of 2005 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued						$ 100,000
Maturity date		Aug. 01, 2029
Gulf Opportunity Zone Act Of 2005 [Member] \| GO Zone 6 1/2% Tax-Exempt Revenue Bonds Due 2035 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued					$ 89,000
Stated interest rate	6.50%
Maturity date	Nov. 01, 2035

Long-Term Debt (IKE Zone Act Senior Notes Due 2035) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2010	Dec. 31, 2015	Dec. 31, 2014	Dec. 02, 2010
Debt Instrument [Line Items]
Stated interest rate		6.50%
Minimum debt amount guaranteed by subsidiaries		$ 5,000
Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member]
Debt Instrument [Line Items]
Stated interest rate		6.50%	6.50%
Minimum debt amount guaranteed by subsidiaries		$ 5,000
Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member] \| Redeemed Prior To November 1, 2020 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called		100.00%
Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member] \| Redeemed On Or After November 1, 2020 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called		100.00%
Emergency Economic Stabilization Act Of 2008 [Member] \| Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued				$ 65,000
Stated interest rate				6.50%
Maturity date	Nov. 01, 2035

Long-Term Debt (GO Zone Act Senior Notes Due 2029) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jul. 31, 2010	Dec. 31, 2015	Dec. 31, 2014	Jul. 02, 2010
Debt Instrument [Line Items]
Stated interest rate		6.50%
Minimum debt amount guaranteed by subsidiaries		$ 5,000
GO Zone 6 1/2% Senior Notes Due 2029 [Member]
Debt Instrument [Line Items]
Stated interest rate		6.50%	6.50%
Senior notes		$ 100,000	$ 100,000
Redeemed Prior To August First Twenty Twenty [Member] \| GO Zone 6 1/2% Senior Notes Due 2029 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called		100.00%
Redeemed On Or After August First Twenty Twenty [Member] \| GO Zone 6 1/2% Senior Notes Due 2029 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called		100.00%
Gulf Opportunity Zone Act Of 2005 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued				$ 100,000
Maturity date	Aug. 01, 2029
Gulf Opportunity Zone Act Of 2005 [Member] \| GO Zone 6 1/2% Senior Notes Due 2029 [Member]
Debt Instrument [Line Items]
Stated interest rate				6.50%

Long-Term Debt (GO Zone Act Senior Notes Due 2032) (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Jul. 31, 2010	Dec. 31, 2007	Dec. 31, 2015	Dec. 31, 2014	Jul. 02, 2010	Dec. 13, 2007
Debt Instrument [Line Items]
Stated interest rate			6.50%
Minimum debt amount guaranteed by subsidiaries			$ 5,000
GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Stated interest rate			6.75%	6.75%
Redeemed Prior To November 1, 2017 [Member] \| GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called			100.00%
Redeemed On Or After November 1, 2017 [Member] \| GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Percentage of principal required if called			100.00%
Gulf Opportunity Zone Act Of 2005 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued					$ 100,000
Maturity date	Aug. 01, 2029
Gulf Opportunity Zone Act Of 2005 [Member] \| GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued						$ 250,000
Stated interest rate						6.75%
Maturity date		Nov. 01, 2032

Long-Term Debt (Debt Covenants And Credit Facility) (Details)	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares
Debt Instrument [Line Items]
Number of credit rating agencies	2
Maximum unrestricted distributions allowable	$ 100,000,000
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Borrowing availability of bank commitments, minimum	$ 50,000,000
Line of Credit Facility, Covenant Terms, Acquisitions And Investments, Borrowing Availability Threshold, Percent Of Commitments, Scenario Two	12.50%
Line of Credit Facility, Covenant Terms, Specified Investments Permissible	$ 50,000,000
Line of Credit Facility, Covenant Terms, Specified Investments Permissible, Percentage Of Tangible Assets And Acquisitions	1.25%
Line of Credit Facility, Covenant Terms, Specified Acquisitions Permissible	$ 100,000,000
Line of Credit Facility, Covenant Terms, Specified Acquisitions Permissible, Percentage Of Tangible Assets	2.50%
Debt Covenant [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Maximum unrestricted quarterly dividends allowable under debt covenants \| $ / shares	0.10
Maximum percentage of income distribution	50.00%
Maximum distribution percentage of specified net cash proceeds	100.00%
Minimum [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Covenant Terms, Acquisitions Restrictions, Borrowing Availability Threshold, Percent Of Commitments, Scenario Two	100.00%
Line of Credit Facility, Covenant Terms, Distributions Restrictions, Borrowing Availability Threshold, Scenario Two	$ 50,000,000
Line of Credit Facility, Covenant Terms, Acquisitions Restrictions, Borrowing Availability Threshold, Percent Of Commitments, Scenario One	15.00%
Maximum [Member] \| Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Covenant Terms, Distributions Restrictions, Borrowing Availability Threshold, Scenario Two	$ 60,000,000
Maximum [Member] \| Debt Covenant [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Fixed charge coverage ratio for debt covenant	2.0

Long-Term Debt (Additional Disclosures) (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 1997	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Weighted average interest rate on all long-term debt		5.50%	5.50%
Waste Disposal Revenue Bonds Due 2027 [Member]
Debt Instrument [Line Items]
Senior notes, principal amount issued	$ 10,889
Maturity	December 2027	2027
Effective interest rate		0.07%	0.05%

Stockholders' Equity (Details)		12 Months Ended
Stockholders' Equity (Details)	Feb. 14, 2014	Dec. 31, 2015 USD ($) vote $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($)	Nov. 20, 2015 USD ($)	Mar. 31, 2015 USD ($) shares	Nov. 30, 2014 USD ($)	May 16, 2014 $ / shares shares	May 15, 2014 shares	Aug. 31, 2011 USD ($)
Class of Stock [Line Items]
Aggregated regular quarterly dividends on common stock		$ 91,551,000	$ 77,656,000	$ 55,236,000
Description of common stock voting rights		Each share of common stock entitles the holder to one vote on all matters on which holders are permitted to vote, including the election of directors. There are no cumulative voting rights.
Description of common stock subscription rights		The Company's common stock has no preemptive or conversion rights or other subscription rights.
Common stock, redemption provision		$ 0
Stock split conversion ratio	2
Common Stock, shares authorized \| shares		300,000,000	300,000,000					300,000,000	150,000,000
Common stock, par value per share \| $ / shares		$ 0.01	$ 0.01					$ 0.01
Common stock, shares issued \| shares		134,663,244	134,679,064
Common stock, sinking fund		$ 0
Common stock, voting rights \| vote		1
Ordinary Dividend [Member]
Class of Stock [Line Items]
Aggregated regular quarterly dividends on common stock		$ 91,551,000	$ 77,656,000	$ 55,236,000
2011 Program [Member]
Class of Stock [Line Items]
Stock repurchase program, authorized amount										$ 100,000,000
Stock repurchase 2011 program, shares repurchased \| shares						1,944,161
Aggregate purchase price of common stock repurchased						$ 100,000,000
2014 Program [Member]
Class of Stock [Line Items]
Stock repurchase program, authorized amount					$ 150,000		$ 250,000,000
Stock repurchase 2014 program, shares repurchase \| shares		2,682,489

Accumulated Other Comprehensive Income Changes in AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, balance	$ 3,561,931	$ 3,201,888	$ 2,418,603	$ 1,872,256
Amounts reclassified from accumulated other comprehensive loss	(475)	(209)	1,681
Net other comprehensive income (loss) for the year	(49,859)	(76,817)	8,224
Benefits Liability, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, balance	(8,607)	(23,442)	(6,696)
Other comprehensive income (loss) before reclassifications	12,877	(17,314)
Amounts reclassified from accumulated other comprehensive loss	1,958	568	1,669
Net other comprehensive income (loss) for the year	14,835	(16,746)
Cumulative Foreign Currency Exchange
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, balance	(115,690)	(56,224)	3,904
Other comprehensive income (loss) before reclassifications	(59,466)	(60,128)
Amounts reclassified from accumulated other comprehensive loss	0	0
Net other comprehensive income (loss) for the year	(59,466)	(60,128)
Net Unrealized Holding Gains on Investments, Net of Tax
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, balance	(4,995)	233	176
Other comprehensive income (loss) before reclassifications	(2,795)	834
Amounts reclassified from accumulated other comprehensive loss	(2,433)	(777)
Net other comprehensive income (loss) for the year	(5,228)	57
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income, balance	(129,292)	(79,433)	$ (2,616)
Other comprehensive income (loss) before reclassifications	(49,384)	(76,608)
Amounts reclassified from accumulated other comprehensive loss	(475)	(209)
Net other comprehensive income (loss) for the year	$ (49,859)	$ (76,817)

Accumulated Other Comprehensive Income Reclassifications in AOCI (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense), net	$ 38,270	$ (2,721)	$ 6,790
Provision for income taxes, investments	(298,396)	(398,902)	(331,747)
Total reclassifications for the period	475	209	(1,681)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of pension and other post-retirement items	0	(347)	(381)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of pension and other post-retirement items	(2,663)	(577)	(2,331)
Accumulated Defined Benefit Plan Adjustment, Settlement Benefits Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of pension and other post-retirement items	(355)	0	0
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amortization of pension and other post-retirement items	(3,018)	(924)	(2,712)
Provision for income taxes, defined benefit plan	1,060	356	1,043
Total reclassifications for the period	(1,958)	(568)	(1,669)
Accumulated Net Investment Gain (Loss) Including Portion Attributable to Noncontrolling Interest [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income (expense), net	3,798	1,212	(19)
Provision for income taxes, investments	(1,365)	(435)	7
Income (Loss) from Continuing Operations, including portion attributable to noncontrolling interest	$ 2,433	$ 777	$ (12)

Employee Benefits (Narrative Defined Contribution Plans) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Foreign Postretirement Benefit Plan [Member]
Defined Contribution Plan [Line Items]
Defined contribution savings plan expense	$ 1,912	$ 416
Defined Contribution Savings Plan [Member] \| U. S. Plans [Member]
Defined Contribution Plan [Line Items]
Maximum employee contribution as a percentage of annual compensation	100.00%
Matching percentage by company of first 4% of employee contribution	100.00%
Percentage of employee contribution fully matched by company	4.00%
Employer contributions to plans	$ 7,594	6,856	$ 6,022
Defined Contribution Retirement Plan [Member] \| U. S. Plans [Member]
Defined Contribution Plan [Line Items]
Employer contributions to plans	$ 11,715	$ 8,309	$ 6,227
Length of service required to be eligible for annual retirement contributions (in years)	1 year

Employee Benefits (Narrative Defined Benefit Plans) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) subsidiary	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Estimated prior service cost to be amortized from other comprehensive income into net periodic benefit cost during 2012	$ 0
Estimated net loss to be amortized from other comprehensive income into net periodic benefit cost during 2012	$ 1,213
Expected return on plan assets	7.00%
Percentage of investments for long-term growth included in investment strategy	55.00%
Percentage of investments for short-term growth included in investment strategy	45.00%
Discretionary range for pension fund trustee included in investment policy	10.00%
Number of subsidiaries company provides post-retirement healthcare benefits to \| subsidiary	2
U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	7.00%	7.00%	7.00%
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated prior service cost to be amortized from other comprehensive income into net periodic benefit cost during 2012	$ 0
Estimated net loss to be amortized from other comprehensive income into net periodic benefit cost during 2012	125
Wage Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	900
Salaried Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected contributions	$ 900
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fixed income, target allocation percentage	55.00%
Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fixed income, target allocation percentage	45.00%
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of pension plans	80.00%
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Funded status of pension plans	100.00%

Employee Benefits (Multiemployer Plans) (Details)
$ in Thousands

12 Months Ended

Dec. 31, 2015

USD ($)

plan

Dec. 31, 2014

USD ($)

Number of multiemployer plans | plan

Contributions to multi-employer plans | $

^[1]

$ 4,489

$ 2,295

[1]

Employee Benefits (Schedule Of Change In Benefit Obligation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation, beginning of year	$ 67,010	$ 57,946
Benefit obligation assumed with acquisition	0	0
Service cost	29	334	$ 1,091
Interest cost	2,015	2,322	2,047
Actuarial (gain) loss	(2,330)	9,165
Benefits paid	(4,532)	(2,757)
Foreign exchange effects	0	0
Benefit obligation, end of year	62,192	67,010	57,946
Non-U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation, beginning of year	122,701	0
Benefit obligation assumed with acquisition	0	117,970
Service cost	1,661	602
Interest cost	2,110	1,366
Actuarial (gain) loss	(17,310)	15,425
Benefits paid	(2,139)	(898)
Foreign exchange effects	(12,202)	(11,764)
Benefit obligation, end of year	94,821	122,701	0
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation, beginning of year	20,177	19,958
Service cost	22	22	30
Interest cost	571	733	623
Actuarial (gain) loss	(1,848)	989
Benefits paid	(1,107)	(1,525)
Benefit obligation, end of year	$ 17,815	$ 20,177	$ 19,958

Employee Benefits (Schedule Of Change In Plan Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, beginning of year	$ 53,415	$ 49,236
Actual return	(268)	2,953
Employer contribution	2,148	3,983
Benefits paid	(4,532)	(2,757)
Fair value of plan assets, end of year	50,763	53,415
Funded status, end of year	(11,429)	(13,595)
Non-U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, beginning of year	0	0
Actual return	0	0
Employer contribution	2,139	898
Benefits paid	(2,139)	(898)
Fair value of plan assets, end of year	0	0
Funded status, end of year	(94,821)	(122,701)
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets, beginning of year	0	0
Employer contribution	1,107	1,525
Benefits paid	(1,107)	(1,525)
Fair value of plan assets, end of year	0	0
Funded status, end of year	$ (17,815)	$ (20,177)

Employee Benefits (Schedule Of Amounts Recognized In The Consolidated Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Noncurrent liabilities	$ (106,250)	$ (136,296)
U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent liabilities	(11,429)	(13,595)
Net amount recognized	(11,429)	(13,595)
Non-U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Noncurrent liabilities	(94,821)	(122,701)
Net amount recognized	(94,821)	(122,701)
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Current liabilities	(1,244)	(1,798)
Noncurrent liabilities	(16,571)	(18,379)
Net amount recognized	$ (17,815)	$ (20,177)

Employee Benefits (Schedule Of Amounts Recognized In Accumulated Other Comprehensive Income) (Details) - USD ($)
$ in Thousands

Dec. 31, 2015

Dec. 31, 2014

Pension Benefits [Member]

Accumulated other comprehensive income, benefits, net of tax

$ 6,812

$ 20,315

U. S. Plans [Member]

Net loss (gain)

14,755

15,482

Foreign exchange effects

Total before tax

^[1]

14,755

15,482

Non-U. S. Plans [Member]

Post-Retirement Healthcare Benefit Plans [Member]

Net loss (gain)

(4,919)

15,425

Foreign exchange effects

1,986

Total before tax

^[1]

(2,933)

15,425

Accumulated other comprehensive income, benefits, net of tax

Net loss (gain)

2,978

5,171

Total before tax

^[2]

2,978

5,171

$ 1,795

$ 3,127

[1]	(1)After-tax totals for pension benefits were $6,812 and $20,315 for 2015 and 2014, respectively, and are reflected in stockholders' equity as accumulated other comprehensive loss.
[2]	After-tax totals for post-retirement healthcare benefits were $1,795 and $3,127 for 2015 and 2014, respectively, and are reflected in stockholders' equity as accumulated other comprehensive loss.

Employee Benefits (Schedule Of Accumulated Benefit Obligations In Excess Of Plan Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ (62,192)	$ (67,010)	$ (57,946)
Accumulated benefit obligation	(62,192)	(67,010)
Fair value of plan assets	50,763	53,415	49,236
Non-U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	(94,821)	(122,701)	0
Accumulated benefit obligation	(93,231)	(119,258)
Fair value of plan assets	$ 0	$ 0	$ 0

Employee Benefits (Schedule Of Net Benefit Costs And Amounts Recognized In Other Comprehensive Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Amortization of net loss	$ (2,663)	$ (924)	$ (2,712)
Settlement benefits	(355)	0	0
U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	29	334	1,091
Interest cost	2,015	2,322	2,047
Expected return on plan assets	(2,960)	(3,140)	(2,854)
Net amortization	1,270	571	2,255
Settlement benefits	355	0	0
Net periodic benefit cost	709	87	2,539
Net loss (gain) emerging	898	9,352	(12,468)
Amortization of net loss	(1,270)	(274)	(1,958)
Amortization of prior service cost	0	(297)	(297)
Settlement benefits	(355)	0	0
Total recognized in OCI	(727)	8,781	(14,723)
Total net periodic benefit cost and OCI	(18)	8,868	(12,184)
Non-U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1,661	602
Interest cost	2,110	1,366
Expected return on plan assets	0	0
Net amortization	1,048	0
Settlement benefits	0	0
Net periodic benefit cost	4,819	1,968
Net loss (gain) emerging	(17,310)	15,425
Amortization of net loss	(1,048)	0
Amortization of prior service cost	0	0
Settlement benefits	0	0
Total recognized in OCI	(18,358)	15,425
Total net periodic benefit cost and OCI	(13,539)	17,393
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	22	22	30
Interest cost	571	733	623
Net amortization	345	353	457
Net periodic benefit cost	938	1,108	1,110
Net loss (gain) emerging	(1,848)	989	(501)
Amortization of net loss	(345)	(303)	(373)
Amortization of prior service cost	0	(50)	(84)
Total recognized in OCI	(2,193)	636	(958)
Total net periodic benefit cost and OCI	$ (1,255)	$ 1,744	$ 152

Employee Benefits (Schedule Of Weighted Average Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	7.00%
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.50%	3.30%	4.00%
Discount rate	3.30%	4.00%	3.00%
U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.00%	3.50%	4.50%
Expected return on plan assets	7.00%	7.00%	7.00%
Rate of compensation increase	0.00%	0.00%	4.00%
Discount rate	3.50%	4.50%	3.30%
Expected return on plan assets	7.00%	7.00%	7.00%
Rate of compensation increase	0.00%	0.00%	4.00%
Non-U. S. Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.40%	1.90%
Expected return on plan assets	0.00%	0.00%
Rate of compensation increase	2.50%	2.50%
Discount rate	1.90%	2.60%
Expected return on plan assets	0.00%	0.00%
Rate of compensation increase	2.50%	2.50%

Employee Benefits (Schedule Of Fair Value Of Pension Plan Assets) (Details) - U. S. Plans [Member] - USD ($)
$ in Thousands

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

$ 50,763

$ 53,415

$ 49,236

Level 2 [Member]

50,763

53,415

Level 3 [Member]

Bank Collective Trust Funds - Equity Securities [Member] | Large-Cap Index Funds [Member]

622

Bank Collective Trust Funds - Equity Securities [Member] | Small-Cap Index Funds [Member]

^[1]

18,384

19,473

Bank Collective Trust Funds - Equity Securities [Member] | International Index Funds [Member]

^[2]

4,069

3,351

Bank Collective Trust Funds - Equity Securities [Member] | Level 2 [Member] | Large-Cap Index Funds [Member]

^[3]

8,181

8,474

Bank Collective Trust Funds - Equity Securities [Member] | Level 2 [Member] | Small-Cap Index Funds [Member]

^[1]

18,384

19,473

Bank Collective Trust Funds - Equity Securities [Member] | Level 2 [Member] | International Index Funds [Member]

^[2]

4,069

3,351

Bank Collective Trust Funds - Fixed Income [Member] | Bond Index Funds [Member]

^[3]

8,181

8,474

Bank Collective Trust Funds - Fixed Income [Member] | Short Term Investment Funds [Member]

^[4]

19,624

21,495

Bank Collective Trust Funds - Fixed Income [Member] | Level 2 [Member] | Bond Index Funds [Member]

505

622

^[4]

$ 19,624

$ 21,495

[1]	(1)Substantially all of the assets of these funds are invested in large-cap U.S. companies. The remainder of the assets of these funds is invested in cash reserves.
[2]	(2)Substantially all of the assets of these funds are invested in small-cap U.S. companies. The remainder of the assets of these funds is invested in cash reserves.
[3]	(3)Substantially all of the assets of these funds are invested in international companies in developed markets (excluding the United States and Canada). The remainder of the assets of these funds is invested in cash reserves.
[4]	(4)This category represents investment grade bonds of U.S. issuers, including U.S. Treasury notes.

Employee Benefits (Schedule Of Estimated Future Benefit Payments) (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Year one	$ 8,159
Year two	7,345
Year three	7,901
Year four	8,461
Year five	7,813
Years 6 to 10	36,897
Post-Retirement Healthcare Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Year one	1,244
Year two	1,408
Year three	1,409
Year four	1,395
Year five	1,363
Years 6 to 10	$ 6,005

Stock-Based Compensation (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 10,196	$ 9,261	$ 6,966
Total intrinsic value of options exercised	1,145	14,534	7,656
Income tax benefit from the exercise of stock options	$ 78	4,512	2,224
Range One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Remaining Contractual Life (Years)	2 years 8 months 12 days
Range Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Remaining Contractual Life (Years)	2 years 7 months 6 days
Range Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Remaining Contractual Life (Years)	5 years 8 months 12 days
Range Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Remaining Contractual Life (Years)	7 years 3 months 18 days
Range Five [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Remaining Contractual Life (Years)	8 years 8 months 12 days
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards, term (in years)	10 years
Unrecognized compensation expense	$ 3,755
Unrecognized compensation expense, weighted-average period of recognition (in years)	1 year 3 months 18 days
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 119
Unrecognized compensation expense, weighted-average period of recognition (in years)	7 months 22 days
Total fair value of shares of restricted stock that vested	$ 8,363	8,831	12,480
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 14,925
Unrecognized compensation expense, weighted-average period of recognition (in years)	2 years 6 months
Total fair value of shares of restricted stock that vested	$ 725	$ 371	$ 14
Ratably On Annual Basis [Member] \| Stock Options [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	1 year
Ratably On Annual Basis [Member] \| Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	4 years
Ratably On Annual Basis [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	3 years
Cliff Vest [Member] \| Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	1 year
Cliff Vest [Member] \| Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	6 years
First One Half Increment On Anniversary Of Award Date [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	5 years
Second One Half Increment On Anniversary Of Award Date [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	9 years 6 months
Second One Half Increment On Anniversary Of Award Date [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation, vesting period	9 years 6 months

Stock-Based Compensation (Schedule Of Option Activity And Changes) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares
Share-based Compensation [Abstract]
Options, Outstanding, beginning balance \| shares	1,179,402
Options, Granted \| shares	168,369
Options, Exercised \| shares	(32,308)
Options, Cancelled \| shares	(47,673)
Options, Outstanding, ending balance \| shares	1,267,790
Options, Exercisable, ending balance \| shares	822,573
Weighted Average Exercise Price, Outstanding, beginning balance \| $ / shares	$ 24.89
Weighted Average Exercise Price, Granted \| $ / shares	67.59
Weighted Average Exercise Price, Exercised \| $ / shares	32.92
Weighted Average Exercise Price, Cancelled \| $ / shares	32.64
Weighted Average Exercise Price, Outstanding, ending balance \| $ / shares	30.07
Weighted Average Exercise Price, Exercisable, ending balance \| $ / shares	$ 19.08
Weighted Average Remaining Term (Years), Outstanding	5 years
Weighted Average Remaining Term (Years), Exercisable	4 years 2 months 12 days
Aggregate Intrinsic Value, Outstanding \| $	$ 34,577
Aggregate Intrinsic Value, Exercisable \| $	$ 29,376

Stock-Based Compensation (Schedule Of Range Of Exercise Prices For Outstanding Options) (Details)	12 Months Ended
	Dec. 31, 2015 $ / shares shares
Range One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 7.12
Range of Prices, Upper Limit	$ 9.65
Options Outstanding \| shares	304,200
Weighted Average Remaining Contractual Life (Years)	2 years 8 months 12 days
Range Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 10.26
Range of Prices, Upper Limit	$ 18.05
Options Outstanding \| shares	349,906
Weighted Average Remaining Contractual Life (Years)	2 years 7 months 6 days
Range Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 22.92
Range of Prices, Upper Limit	$ 30.05
Options Outstanding \| shares	191,292
Weighted Average Remaining Contractual Life (Years)	5 years 8 months 12 days
Range Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 40.38
Range of Prices, Upper Limit	$ 52.35
Options Outstanding \| shares	107,562
Weighted Average Remaining Contractual Life (Years)	7 years 3 months 18 days
Range Five [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of Prices, Lower Limit	$ 63.98
Range of Prices, Upper Limit	$ 68.18
Options Outstanding \| shares	314,830
Weighted Average Remaining Contractual Life (Years)	8 years 8 months 12 days

Stock-Based Compensation (Schedule Of Weighted Average Value And Assumptions For Fair Value Of Options) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value	$ 20.21	$ 20.49	$ 17.03
Risk-free interest rate	1.70%	1.60%	0.90%
Expected life in years	5 years	5 years	5 years
Expected volatility	34.20%	35.70%	44.50%
Expected dividend yield	0.90%	0.70%	0.60%

Stock-Based Compensation (Schedule Of Non-Vested Restricted Stock Award and RSU Activity and Changes) (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Non-vested, beginning balance	205,056
Number of Shares, Vested	(124,380)
Number of Shares, Forfeited	(15,820)
Number of Shares, Non-vested, ending balance	64,856	205,056
Weighted Average Grant Date Fair Value, Non-vested, beginning balance	$ 24.52
Weighted Average Grant Date Fair Value, Vested	30.17
Weighted Average Grant Date Fair Value, Forfeited	15.81
Weighted Average Grant Date Fair Value, Non-vested, ending balance	$ 15.81	$ 24.52
Unrecognized Stock-based Compensation Expense Related to Non-Vested RSU	$ 119
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	7 months 22 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 8,363	$ 8,831	$ 12,480
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares, Non-vested, beginning balance	422,000
Number of Shares, Granted	100,258
Number of Shares, Vested	(12,277)
Number of Shares, Forfeited	(11,109)
Number of Shares, Non-vested, ending balance	498,872	422,000
Weighted Average Grant Date Fair Value, Non-vested, beginning balance	$ 55.75
Weighted Average Grant Date Fair Value, Granted	65.77
Weighted Average Grant Date Fair Value, Vested	61.08
Weighted Average Grant Date Fair Value, Forfeited	56.82
Weighted Average Grant Date Fair Value, Non-vested, ending balance	$ 57.61	$ 55.75
Unrecognized Stock-based Compensation Expense Related to Non-Vested RSU	$ 14,925
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	2 years 6 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 725	$ 371	$ 14

Derivative Commodity Instruments (Narrative) (Details) - instrument	Dec. 31, 2015	Dec. 31, 2014
Commodity Forward Contracts [Member] \| Designated As Fair Value Hedges [Member]
Derivative [Line Items]
Number of derivative instruments designated as fair value hedges	0	0

Derivative Commodity Instruments (Fair Values Of Derivative Instruments In Consolidated Balance Sheets) (Details) - Derivatives Not Designated As Hedging Instrument [Member] - Commodity Forward Contracts [Member] - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Total asset derivatives	$ 5,553	$ 3,145
Total liability derivatives	21,762	10,108
Accounts Receivable, Net [Member]
Derivative [Line Items]
Total asset derivatives	3,465	3,145
Other Assets [Member]
Derivative [Line Items]
Total asset derivatives	2,088	0
Accrued Liabilities [Member]
Derivative [Line Items]
Total liability derivatives	9,325	6,549
Other Liabilities [Member]
Derivative [Line Items]
Total liability derivatives	$ 12,437	$ 3,559

Derivative Commodity Instruments (Impact Of Derivative Instruments Designated As Fair Value Hedges) (Details) - Designated As Fair Value Hedges [Member] - Cost of Sales [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2013 USD ($)
Commodity Forward Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	$ (303)
Firm Commitment Hedged Items [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	$ 143

Derivative Commodity Instruments (Impact Of Derivative Instruments Not Designated As Fair Value Hedges) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commodity Forward Contracts [Member] \| Derivatives Not Designated As Hedging Instrument [Member] \| Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	$ (11,395)	$ (9,678)	$ 5,438

Derivative Commodity Instruments Derivative Commodity Instruments (Offsetting Asset) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Offsetting Assets [Line Items]
Derivative assets subject to enforceable master netting arrangements	$ 0	$ 2,333
Derivative assets not subject to enforceable master netting arrangements	462	111
Total asset derivatives	462	2,444
Gross amounts not offset in the consolidated balance sheet	0	0
Derivative Asset, net amount offset against collateral	0	2,333
Commodity Forward Contracts [Member]
Offsetting Assets [Line Items]
Derivative assets subject to enforceable master netting arrangements	0	2,333
Gross amounts of recognized assets	5,091	3,034
Gross amounts offset in the consolidated balance sheet	(5,091)	(701)
Subject to Master Netting [Member] \| Commodity Forward Contracts [Member] \| Counterparty A [Member]
Offsetting Assets [Line Items]
Derivative assets subject to enforceable master netting arrangements	0	2,333
Gross amounts not offset in the consolidated balance sheet	0	0
Derivative Asset, net amount offset against collateral	$ 0	$ 2,333

Derivative Commodity Instruments Derivative Commodity Instruments (Offsetting Liability) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Offsetting Liabilities [Line Items]
Derivative liabilities subject to enforceable master netting arrangements	$ 5,803	$ 1,490
Derivative liabilities not subject to enforceable master netting arrangements	10,868	7,917
Total derivative liabilities	16,671	9,407
Gross amounts not offset in the consolidated balance sheet	0	0
Derivative liability, net amount offset against collateral	5,803	1,490
Commodity Forward Contracts [Member]
Offsetting Liabilities [Line Items]
Derivative liabilities subject to enforceable master netting arrangements	5,803	1,490
Gross amounts of recognized liabilities	10,894	2,191
Gross amounts offset in the consolidated balance sheet	(5,091)	(701)
Subject to Master Netting [Member] \| Commodity Forward Contracts [Member] \| Counterparty A [Member]
Offsetting Liabilities [Line Items]
Derivative liabilities subject to enforceable master netting arrangements	5,564	1,490
Gross amounts not offset in the consolidated balance sheet	0	0
Derivative liability, net amount offset against collateral	5,564	1,490
Subject to Master Netting [Member] \| Commodity Forward Contracts [Member] \| Counterparty B [Member]
Offsetting Liabilities [Line Items]
Derivative liabilities subject to enforceable master netting arrangements	239	0
Gross amounts not offset in the consolidated balance sheet	0	0
Derivative liability, net amount offset against collateral	$ 239	$ 0

Fair Value Measurements (Schedule Of Assets And Liabilities On A Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Risk management assets	$ 462	$ 2,444
Risk management liabilities	(16,671)	(9,407)
Available-for-sale Securities	568,225	15,414
Fair Value, Measurements, Recurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale Securities	568,225	15,414
Fair Value, Measurements, Recurring [Member] \| Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale Securities	48,081	15,414
Fair Value, Measurements, Recurring [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale Securities	520,144	0
Commodity Forward Contracts [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Risk management assets	5,553	3,145
Risk management liabilities	(21,762)	(10,108)
Commodity Forward Contracts [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Risk management assets	5,553	3,143
Risk management liabilities	(11,648)	0
Commodity Forward Contracts [Member] \| Fair Value, Measurements, Recurring [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Risk management assets	0	2
Risk management liabilities	$ (10,114)	$ (10,108)

Fair Value Measurements (Schedule Of Carrying And Fair Values Of Long-Term Debt) (Details) - USD ($) $ in Thousands		1 Months Ended	12 Months Ended
	Jul. 17, 2012	Dec. 31, 1997	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate			6.50%
3.60% Senior Notes Due 2022 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, Carrying Value			$ 249,226	$ 249,108
Senior Notes, Fair Value			$ 244,828	$ 248,630
Stated interest rate	3.60%		3.60%	3.60%	3.60%
Maturity date	2022		2022
GO Zone 6 1/2% Senior Notes Due 2029 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, Carrying Value			$ 100,000	$ 100,000
Senior Notes, Fair Value			$ 117,153	$ 116,384
Stated interest rate			6.50%	6.50%
Maturity date			2029
GO Zone 6 3/4% Senior Notes Due 2032 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, Carrying Value			$ 250,000	$ 250,000
Senior Notes, Fair Value			$ 268,490	$ 285,545
Stated interest rate			6.75%	6.75%
Maturity date			2032
GO Zone 6 1/2% Tax-Exempt Revenue Bonds Due 2035 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, Carrying Value			$ 89,000	$ 89,000
Senior Notes, Fair Value			$ 106,491	$ 106,504
Stated interest rate			6.50%	6.50%
Maturity date			2035
Ike Zone Six Point Five Percent Tax Exempt Revenue Bonds Due Twenty Thirty Five [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes, Carrying Value			$ 65,000	$ 65,000
Senior Notes, Fair Value			$ 76,741	$ 77,784
Stated interest rate			6.50%	6.50%
Maturity date			2035
Waste Disposal Revenue Bonds Due 2027 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans, Carrying Value			$ 10,889	$ 10,889
Loans, Fair Value			$ 10,889	$ 10,889
Maturity date		December 2027	2027

Income Taxes (Narrative) (Details) $ in Thousands	12 Months Ended
Income Taxes (Narrative) (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Income Tax Disclosure [Abstract]
Foreign and state net operating loss carryforwards	$ 267,192
Net operating loss carryforwards, change in valuation allowance	$ 5,334

Income Taxes (Components Of Income (Loss) Before Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Domestic	$ 880,044	$ 1,102,101	$ 944,378
Foreign	83,397	(18,183)	(2,206)
Income before income taxes	$ 963,441	$ 1,083,918	$ 942,172

Income Taxes (Schedule Of The Provision For (Benefit From) Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Federal, Current	$ 225,617	$ 300,610	$ 215,903
State, Current	23,966	37,351	22,249
Foreign, Current	9,029	1,974	(137)
Total Current	258,612	339,935	238,015
Federal, Deferred	29,820	40,950	94,471
State, Deferred	2,807	22,714	(556)
Foreign, Deferred	7,157	(4,697)	(183)
Total Deferred	39,784	58,967	93,732
Provision for income taxes	$ 298,396	$ 398,902	$ 331,747

Income Taxes (Reconciliation Of Taxes Computed At The Statutory Rate To Income Tax Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Provision for federal income tax at statutory rate	$ 337,204	$ 379,371	$ 329,760
State income tax provision net of federal income tax effect	17,403	40,012	14,364
Foreign income tax rate differential	(13,002)	3,640	519
Manufacturing deduction	(24,185)	(24,465)	(16,275)
Contingent tax liability	0	(1,626)	(404)
Noncontrolling interests	(6,662)	(2,255)	0
Other, net	(12,362)	4,225	3,783
Provision for income taxes	$ 298,396	$ 398,902	$ 331,747

Income Taxes (Schedule Of Deferred Tax Assets And Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Net operating loss carryforward	$ 17,679	$ 18,200
Credit carryforward	746	694
Accruals	62,204	62,845
Allowance for doubtful accounts	4,617	1,998
Inventories	8,663	11,437
Other	7,747	7,660
Deferred taxes assets, total	101,656	102,834
Property, plant and equipment	(423,381)	(398,683)
Turnaround costs	(1,467)	(2,289)
Basis difference—consolidated partnerships	(200,627)	(194,480)
Deferred tax liabilities—total	(625,475)	(595,452)
Valuation allowance	(16,345)	(11,011)
Total net deferred tax liabilities	(540,164)	(503,629)
Balance sheet classifications
Current deferred tax asset	35,439	32,437
Noncurrent deferred tax liability	$ (575,603)	$ (536,066)

Income Taxes (Schedule Of Changes In Gross Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Beginning balance	$ 0	$ 2,501
Reductions due to statutes of limitations expiring	0	(2,501)
Ending balance	$ 0	$ 0

Earnings Per Share (Narrative) (Details) - shares	12 Months Ended
Earnings Per Share (Narrative) (Details) - shares	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Options excluded from computation of earnings per share, shares	301,969	126,091	119,452

Earnings Per Share (Schedule Of Net Income Attributable To Common Stockholders) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Net income attributable to Westlake Chemical Corporation	$ 110,969	$ 183,604	$ 205,095	$ 146,342	$ 183,291	$ 167,757	$ 169,443	$ 158,032	$ 646,010	$ 678,523	$ 610,425
Less: Net income attributable to participating securities									(2,825)	(1,502)	(2,562)
Net income attributable to common shareholders									$ 643,185	$ 677,021	$ 607,863

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

Weighted average common shares - basic

Earnings Per Share (Reconciliation Of Denominator For Basic And Diluted Earnings (Loss) Per Share) (Details) - $ / shares

3 Months Ended

12 Months Ended

Dec. 31, 2015

^[1]

Sep. 30, 2015

^[1]

Jun. 30, 2015

^[1]

Mar. 31, 2015

^[1]

Dec. 31, 2014

^[1]

Sep. 30, 2014

^[1]

Jun. 30, 2014

^[1]

Mar. 31, 2014

^[1]

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Earnings Per Share [Abstract]

131,823,707

133,111,230

133,224,256

Plus incremental shares from: Assumed exercise of options

478,105

532,184

554,994

Weighted average common shares - diluted

132,301,812

133,643,414

133,779,250

Basic

$ 0.85

$ 1.39

$ 1.55

$ 1.10

$ 1.38

$ 1.26

$ 1.27

$ 1.18

$ 4.88

$ 5.09

$ 4.57

Diluted

$ 0.84

$ 1.39

$ 1.54

$ 1.10

$ 1.37

$ 1.25

$ 1.26

$ 1.18

$ 4.86

$ 5.07

$ 4.55

[1]

Basic and diluted earnings per common share ("EPS") for each quarter is computed using the weighted average shares outstanding during that quarter, while EPS for the year is computed using the weighted average shares outstanding for the year. As a result, the sum of the EPS for each of the four quarters may not equal the EPS for the year.

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

Accrued incentive compensation

Supplemental Information (Details) - USD ($)
$ in Thousands

12 Months Ended

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Accrued Liabilities

Accrued liabilities

$ 287,313

$ 276,118

Accrued rebates

46,460

49,900

41,168

37,626

Other Liabilities [Abstract]

Other liabilities

150,961

174,859

Non-current pension obligation

106,250

136,296

Other Income, Net

Interest income

6,034

3,468

$ 3,086

Dividend income

3,559

532

Foreign exchange currency gains (losses), net

^[1]

1,828

(7,382)

(1,375)

Income from equity method investees

6,242

5,883

4,914

Impairment of equity method investment

(4,925)

(6,747)

Gain on acquisition and related expenses, net

20,430

Gain (losses) from sales of securities, net

3,798

1,212

(19)

Other

1,304

313

184

Interest paid, net of interest capitalized

38,270

(2,721)

6,790

Cash Flow Information

31,946

35,336

16,426

Income taxes paid

314,186

314,745

$ 251,599

Fair value of assets acquired

44,013

961,823

Fair value of investment before business combination, net of preexisting balances

(10,352)

Noncontrolling Interest Acquired

(1,597)

Cash paid

(5,518)

(736,224)

Liabilities assumed

$ 26,546

$ 225,599

[1]	Aggregate foreign exchange currency gains and losses included in the consolidated statements of operations for the years ended December 31, 2015, 2014 and 2013.

Related Party And Affiliate Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Dividends received from equity method investments	$ 5,610	$ 5,459	$ 5,114
Affiliates [Member]
Related Party Transaction [Line Items]
Incurred and paid lease payments	2,148	2,001	1,614
Accounts payable due to related parties	$ (196)	(179)
Cypress Interstate Pipeline L.L.C [Member]
Related Party Transaction [Line Items]
Ownership interest	50.00%
American Air Liquide Holdings, Inc. [Member]
Related Party Transaction [Line Items]
Purchases and lease expense to related parties			16,407
Cypress Interstate Pipeline L.L.C [Member] \| Corporate Joint Venture [Member]
Related Party Transaction [Line Items]
Pipeline fees incurred for usage			$ 13,328
InfraServ Knapsack GmbH & Co. KG [Member] \| Affiliates [Member]
Related Party Transaction [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	15.00%
InfraServ Gendorf GmbH & Co. KG [Member] \| Affiliates [Member]
Related Party Transaction [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	11.00%
EPS Ethylene Pipeline Süd GmbH & Co. KG [Member] \| Affiliates [Member]
Related Party Transaction [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	10.00%
American Air Liquide Holdings [Member] \| American Air Liquide Holdings, Inc. [Member]
Related Party Transaction [Line Items]
Accounts payable due to related parties	$ (762)	0
Purchases and lease expense to related parties	10,345	13,862
Pipeline Fees For Transport Of Natural Gas Liquid Feedstocks [Member] \| Cypress Interstate Pipeline L.L.C [Member] \| Corporate Joint Venture [Member]
Related Party Transaction [Line Items]
Pipeline fees incurred for usage	14,110	14,206
Accounts payable due to affiliate	(991)	0
Electricity And Technical Services [Member] \| InfraServ Knapsack & Gendorf GmbH & Co. KG [Member] \| Affiliates [Member]
Related Party Transaction [Line Items]
Accounts payable due to affiliate	(22,931)	(14,161)
Purchases from related parties	115,961	55,400
Pipeline Fees For Transport Of Ethylene Feedstocks [Member] \| EPS Ethylene Pipeline Süd GmbH & Co. KG [Member] \| Affiliates [Member]
Related Party Transaction [Line Items]
Accounts payable due to affiliate	0	(12)
Purchases from related parties	$ 1,022	$ 548

Insurance Recovery (Details) $ in Thousands	12 Months Ended
Insurance Recovery (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Insurance Recovery [Abstract]
Insurance recoveries	$ 7,809

Westlake Chemical Partners LP (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Aug. 04, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Approximate proceeds from sale of units		$ 0	$ 286,088	$ 0
Westlake Chemical Partners LP [Member] \| IPO [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Limited partner interest	52.20%
Westlake Chemical Partners LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Percentage sold to public in IPO	47.80%
Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Limited partner interest	89.40%	86.70%
Westlake Chemical Partners LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Net proceeds distributed to the Company from the initial public offering	$ 230,669
Westlake Chemical Partners LP [Member] \| IPO [Member] \| Subsidiaries [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Number of units sold in public offering	12,937,500
Price per unit	$ 24
Approximate proceeds from sale of units	$ 286,088
Estimated offering expenses from sale of partnership units	$ (24,412)
Limited partner interest	10.60%
Total proceeds from the initial public offering	$ 310,500
Westlake Chemical Partners LP [Member] \| Over-Allotment Option [Member] \| Subsidiaries [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Number of units sold in public offering	1,687,500
Subsidiary of Common Parent [Member] \| Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Subsidiaries [Member] \| Limited Partner [Member]
Related Party Transaction [Line Items]
Limited partner interest	10.60%	13.30%
Cash Reserve Turnaround [Member] \| Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Amount used from proceeds	$ (55,419)
Preformation Capital Expenditure [Member] \| Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Amount used from proceeds	(151,729)
Intercompany Debt [Member] \| Westlake Chemical OpCo LP [Member] \| IPO [Member] \| Subsidiaries [Member]
Related Party Transaction [Line Items]
Amount used from proceeds	$ (78,940)

Acquisitions (Narrative) (Details) $ in Thousands, lb in Millions			5 Months Ended	12 Months Ended
	Jun. 01, 2015 USD ($) lb	Jul. 31, 2014 USD ($) lb	Dec. 31, 2014 USD ($)	Dec. 31, 2014 USD ($)
Suzhou Huasu Plastics Company Ltd [Member]
Business Acquisition [Line Items]
Net gains (loss) on fair value remeasurement	$ (1,505)
Fair value of consideration transferred-cash	5,518
Bargain purchase gain on acquisition	22,550
Fair value of accounts receivable	2,515
Gross contractual amount of accounts receivable	3,006
Uncollectible accounts receivable	(491)
Total purchase consideration	$ 17,467
Vinnolit [Member]
Business Acquisition [Line Items]
Fair value of consideration transferred-cash		$ 309,619
Fair value of accounts receivable		181,890
Gross contractual amount of accounts receivable		183,833
Net sales contributed by acquired business since acquisition date			$ 431,407
Net loss contributed by acquired business since acquisition date			$ (3,718)
Transaction related costs				$ 13,427
Total purchase consideration		$ 736,224
PVC Resin Member [Member] \| Suzhou Huasu Plastics Company Ltd [Member]
Business Acquisition [Line Items]
Combined annual capacity \| lb	300
PVC Resin Member [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Combined annual capacity \| lb		1,700
PVC Film [Member] \| Suzhou Huasu Plastics Company Ltd [Member]
Business Acquisition [Line Items]
Combined annual capacity \| lb	145
Vinyl Chloride Monomer [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Combined annual capacity \| lb		1,500
Caustic Soda [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Combined annual capacity \| lb		1,000
Suzhou Huasu Plastics Company Ltd [Member] \| Affiliates [Member]
Business Acquisition [Line Items]
Percentage of interests acquired	35.70%
Percentage of interest	95.00%
Ownership interest	59.30%

Acquisitions (Assets Acquired and Liabilities Assume - Huasu) (Details) - Suzhou Huasu Plastics Company Ltd [Member] $ in Thousands	Jun. 01, 2015 USD ($)
Business Acquisition [Line Items]
Fair value of consideration transferred-cash	$ 5,518
Preexisting balances between the Company and Huasu, net	(8,538)
Fair value of the Company's investment in Huasu before the business combination, net of preexisting balance	18,890
Fair value of the noncontrolling interest in Huasu	1,597
Cash consideration transferred, preexisting balances, fair value of existing interest and fair value of noncontrolling interest total	17,467
Cash	21,300
Working capital, excluding inventory and cash	5,461
Inventories	17,717
Property, plant and equipment	19,786
Other assets	7,760
Notes payable to banks	(21,085)
Total identifiable net assets	40,017
Bargain purchase gain on acquisition	$ 22,550

Acquisitions (Pro Forma Information) (Details) - Vinnolit [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Net sales	$ 5,152,806	$ 4,976,998
Net income	737,913	666,202
Net income attributable to noncontrolling interests	6,493	0
Net income attributable to Westlake Chemical Corporation	$ 731,420	$ 666,202
Earnings per common share attributable to Westlake Chemical Corporation:
Basic	$ 5.48	$ 4.98
Diluted	$ 5.46	$ 4.96

Acquisitions (Assets Acquired and Liabilities Assumed - Vinnolit) (Details) - USD ($) $ in Thousands	Jul. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill		$ 62,016	$ 62,016	$ 62,016
Vinnolit [Member]
Business Acquisition [Line Items]
Cash paid to Sellers	$ 309,619
Cash deposited in escrow	13,390
Retirement of long-term debt as of July 31, 2014, on behalf of the Sellers	413,215
Total purchase consideration	736,224
Cash	125,137
Working capital, excluding inventory and cash	15,373
Inventories	114,961
Property, plant and equipment	469,484
Investments	51,552
Other assets	76,828
Deferred income tax asset - current	7,909
Deferred income tax asset - non-current	27,387
Pension obligation	(117,970)
Other long-term liabilities	(10,723)
Power purchase agreement liability	(10,826)
Deferred income tax liability - current	(6,845)
Deferred income tax liability - non-current	(79,235)
Total identifiable net assets	736,224
Goodwill	0
Consideration transferred	736,224
Fair value of accounts receivable	181,890
Gross contractual amount of accounts receivable	183,833
Uncollectable accounts receivable	1,943
Adjustment to inventory fair value	$ 16,900
Weighted-average life of forward purchase contracts	3 years
Trademarks and Trade Names [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Intangible assets	$ 40,170
Developed Technology Rights [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Intangible assets	31,600
Other [Member] \| Vinnolit [Member]
Business Acquisition [Line Items]
Intangible assets	$ 1,422

Commitments And Contingencies (Narrative) (Details) $ in Thousands	12 Months Ended			101 Months Ended
	Dec. 31, 2015 USD ($) claim	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2015
Loss Contingencies [Line Items]
Minimum Time Between Arbitrations	5 years
Loss Contingency, Claims Settled, Number \| claim	2
Operating lease rental expense	$ 69,455	$ 56,014	$ 45,361
Pending Litigation [Member]
Loss Contingencies [Line Items]
Approximate value of damages sought	1,400
Threatened Litigation [Member]
Loss Contingencies [Line Items]
Amount of settlement	192
PolyOne [Member]
Loss Contingencies [Line Items]
Percentage of costs related to environmental issues to be paid by PolyOne				100.00%
Costs incurred environmental remediation services	$ 2,210	$ 2,805	$ 3,284

Commitments And Contingencies (Future Minimum Lease Commitments) (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Operating Leases
2016	$ 43,200
2017	42,293
2018	35,119
2019	29,164
2020	24,124
Thereafter	582,327
Total minimum lease payments	756,227
Capital Leases
2016	245
2017	245
2018	245
2019	245
2020	245
Thereafter	779
Total minimum lease payments	2,004
Less: Imputed interest costs	(519)
Present value of net minimum lease payments	$ 1,485

Commitments And Contingencies (Minimum Purchase Obligations) (Details) $ in Thousands	Dec. 31, 2015 USD ($)
Unconditional purchase obligations
2016	$ 184,581
2017	194,434
2018	176,230
2019	149,194
2020	$ 141,352

Segment And Geographic Information (Narrative) (Details)	12 Months Ended
	Dec. 31, 2015 plant customer Segment	Dec. 31, 2014 customer	Dec. 31, 2013 customer
Segment Reporting Information [Line Items]
Number of segments \| Segment	2
Number of plants \| plant	11
Olefins [Member]
Segment Reporting Information [Line Items]
Number of major customers	0	0	0
Vinyls [Member]
Segment Reporting Information [Line Items]
Number of major customers	0	0	0

Segment And Geographic Information (Segment Reporting Information) (Details) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

$ 986,766

$ 1,188,037

$ 1,185,002

$ 1,103,531

$ 1,135,871

$ 1,253,227

$ 998,576

$ 1,027,676

$ 4,463,336

^[1]

$ 4,415,350

^[1]

$ 3,759,484

^[1]

Intersegment sales

108,354

147,924

322,411

$ 181,145

$ 254,028

$ 295,374

$ 229,280

$ 302,387

$ 306,761

$ 266,788

$ 248,055

959,827

1,123,991

953,464

245,757

208,486

157,808

38,270

(2,721)

6,790

298,396

398,902

331,747

491,426

431,104

679,222

Olefins [Member]

2,260,113

2,723,690

2,553,669

Intersegment sales

106,861

146,539

320,909

747,436

1,013,825

833,249

110,684

106,244

102,938

4,656

6,102

7,410

242,516

354,159

288,214

304,873

188,729

145,542

Vinyls [Member]

2,203,223

1,691,660

1,205,815

Intersegment sales

1,493

1,385

1,502

254,452

142,740

154,684

134,546

101,666

54,371

8,540

2,680

(1,858)

64,456

52,249

48,296

Corporate And Other [Member]

176,582

237,992

531,939

(42,061)

(32,574)

(34,469)

527

576

499

25,074

(11,503)

1,238

(8,576)

(7,506)

(4,763)

Polyethylene [Member] | Olefins [Member]

9,971

4,383

1,741

Ethylene, Styrene And Other [Member] | Olefins [Member]

1,650,964

1,922,535

1,750,292

PVC, Caustic Soda And Other [Member] | Vinyls [Member]

609,149

801,155

803,377

Building Products [Member] | Vinyls [Member]

1,718,359

1,203,332

800,658

Revenues from External Customers and Long-Lived Assets [Line Items]

$ 484,864

$ 488,328

$ 405,157

[1]	Revenues are attributed to countries based on location of customer.

Segment And Geographic Information (Capital Expenditures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Capital expenditures	$ 491,426	$ 431,104	$ 679,222
Olefins [Member]
Segment Reporting Information [Line Items]
Capital expenditures	304,873	188,729	145,542
Vinyls [Member]
Segment Reporting Information [Line Items]
Capital expenditures	176,582	237,992	531,939
Corporate And Other [Member]
Segment Reporting Information [Line Items]
Capital expenditures	$ 9,971	$ 4,383	$ 1,741

Segment And Geographic Information (Total Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total assets	$ 5,575,252	$ 5,213,990
Olefins [Member]
Segment Reporting Information [Line Items]
Total assets	1,869,888	1,785,895
Vinyls [Member]
Segment Reporting Information [Line Items]
Total assets	2,638,833	2,618,646
Corporate And Other [Member]
Segment Reporting Information [Line Items]
Total assets	$ 1,066,531	$ 809,449

Segment And Geographic Information (Reconciliation Of Total Segment Income From Operations To Consolidated Income Before Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting [Abstract]
Income from operations for reportable segments	$ 181,145	$ 254,028	$ 295,374	$ 229,280	$ 302,387	$ 306,761	$ 266,788	$ 248,055	$ 959,827	$ 1,123,991	$ 953,464
Interest expense									(34,656)	(37,352)	(18,082)
Other income, (expense), net									38,270	(2,721)	6,790
Income (Loss) from Continuing Operations before Income Taxes									$ 963,441	$ 1,083,918	$ 942,172

Segment and Geographic Information (Geographic Information for Sales to External Customers and Long-lived Assets) (Details) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

$ 986,766

$ 1,188,037

$ 1,185,002

$ 1,103,531

$ 1,135,871

$ 1,253,227

$ 998,576

$ 1,027,676

$ 4,463,336

^[1]

$ 4,415,350

^[1]

$ 3,759,484

^[1]

Revenues from External Customers and Long-Lived Assets [Line Items]

3,004,067

2,757,557

3,004,067

2,757,557

United States [Member]

^[1]

3,133,395

3,596,091

3,404,378

Revenues from External Customers and Long-Lived Assets [Line Items]

2,588,366

2,319,572

2,588,366

2,319,572

Canada [Member]

Revenues from External Customers and Long-Lived Assets [Line Items]

^[1]

195,790

217,567

214,162

GERMANY

^[1]

394,459

198,921

3,942

Revenues from External Customers and Long-Lived Assets [Line Items]

379,262

417,702

379,262

417,702

Switzerland [Member]

Revenues from External Customers and Long-Lived Assets [Line Items]

^[1]

106,750

89,214

54,637

ITALY

Revenues from External Customers and Long-Lived Assets [Line Items]

90,237

36,823

FRANCE

Other Foreign Countries [Member]

58,727

27,521

8,207

Revenues from External Customers and Long-Lived Assets [Line Items]

^[1]

483,978

249,213

$ 74,103

Condensed Financial Statements, Captions [Line Items]

$ 36,439

$ 20,283

$ 36,439

$ 20,283

[1]	Revenues are attributed to countries based on location of customer.

Guarantor Disclosures (Narrative) (Details) - USD ($) $ in Thousands			12 Months Ended
	Aug. 04, 2014	Jul. 17, 2012	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2012
Condensed Financial Statements, Captions [Line Items]
Stated interest rate			6.50%
3.60% Senior Notes Due 2022 [Member]
Condensed Financial Statements, Captions [Line Items]
Stated interest rate		3.60%	3.60%	3.60%	3.60%
Maturity		2022	2022
Senior notes, minimum debt amount guaranteed by subsidiaries			$ 5,000
Subsidiaries [Member] \| Limited Partner [Member] \| IPO [Member] \| Westlake Chemical Partners LP [Member]
Condensed Financial Statements, Captions [Line Items]
Limited partner interest	10.60%

Guarantor Disclosures (Condensed Consolidating Financial Information Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	$ 662,525	$ 880,601	$ 461,301	$ 790,078
Marketable securities	520,144	0
Accounts receivable, net	508,532	560,666
Inventories	434,060	525,776
Prepaid expenses and other current assets	14,489	11,807
Deferred income taxes	35,439	32,437
Total current assets	2,175,189	2,011,287
Property, plant and equipment, net	3,004,067	2,757,557
Equity investments	9,208	61,305
Other assets, net	386,788	383,841
Total assets	5,575,252	5,213,990
Accounts and notes payable	235,329	261,062
Accrued liabilities	287,313	276,118
Total current liabilities	522,642	537,180
Long-term debt	764,115	763,997
Deferred income taxes	575,603	536,066
Other liabilities	150,961	174,859
Liabilities	2,013,321	2,012,102
Stockholders' equity	3,265,878	2,911,511
Noncontrolling interests	296,053	290,377
Total equity	3,561,931	3,201,888	2,418,603	1,872,256
Total liabilities and equity	5,575,252	5,213,990
Westlake Chemical Corporation [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	303,131	655,947	420,948	753,881
Marketable securities	520,144
Accounts receivable, net	10,943	8,451
Inventories	0	0
Prepaid expenses and other current assets	2,201	172
Deferred income taxes	702	409
Total current assets	837,121	664,979
Property, plant and equipment, net	0	0
Equity investments	4,991,167	4,033,378
Other assets, net	17,896	30,543
Total assets	5,846,184	4,728,900
Accounts and notes payable	1,817,963	1,055,527
Accrued liabilities	9,117	8,754
Total current liabilities	1,827,080	1,064,281
Long-term debt	753,226	753,108
Deferred income taxes	0	0
Other liabilities	0	0
Liabilities	2,580,306	1,817,389
Stockholders' equity	3,265,878	2,911,511
Noncontrolling interests	0	0
Total equity	3,265,878	2,911,511
Total liabilities and equity	5,846,184	4,728,900
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	6,828	3,057	6,227	6,973
Marketable securities	0
Accounts receivable, net	2,183,276	1,454,709
Inventories	326,588	414,975
Prepaid expenses and other current assets	12,166	9,485
Deferred income taxes	32,787	29,832
Total current assets	2,561,645	1,912,058
Property, plant and equipment, net	1,567,897	1,477,515
Equity investments	1,207,679	1,237,080
Other assets, net	450,428	387,325
Total assets	5,787,649	5,013,978
Accounts and notes payable	121,820	160,834
Accrued liabilities	195,785	203,608
Total current liabilities	317,605	364,442
Long-term debt	10,889	10,889
Deferred income taxes	532,837	497,919
Other liabilities	49,334	43,452
Liabilities	910,665	916,702
Stockholders' equity	4,876,984	4,097,276
Noncontrolling interests	0	0
Total equity	4,876,984	4,097,276
Total liabilities and equity	5,787,649	5,013,978
Westlake Chemical OpCo LP [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	163,430	131,545	0	0
Marketable securities	0
Accounts receivable, net	51,582	56,049
Inventories	3,879	6,634
Prepaid expenses and other current assets	267	212
Deferred income taxes	0	0
Total current assets	219,158	194,440
Property, plant and equipment, net	1,020,469	842,057
Equity investments	0	0
Other assets, net	44,157	57,733
Total assets	1,283,784	1,094,230
Accounts and notes payable	33,901	17,680
Accrued liabilities	21,873	11,225
Total current liabilities	55,774	28,905
Long-term debt	248,665	227,638
Deferred income taxes	1,392	1,848
Other liabilities	0	0
Liabilities	305,831	258,391
Stockholders' equity	977,953	835,839
Noncontrolling interests	0	0
Total equity	977,953	835,839
Total liabilities and equity	1,283,784	1,094,230
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	189,136	90,052	34,126	29,224
Marketable securities	0
Accounts receivable, net	113,321	135,133
Inventories	103,593	104,167
Prepaid expenses and other current assets	2,734	1,938
Deferred income taxes	1,950	2,196
Total current assets	410,734	333,486
Property, plant and equipment, net	415,701	437,985
Equity investments	469,915	352,550
Other assets, net	129,539	141,948
Total assets	1,425,889	1,265,969
Accounts and notes payable	87,510	95,856
Accrued liabilities	88,142	77,372
Total current liabilities	175,652	173,228
Long-term debt	0	0
Deferred income taxes	47,941	42,369
Other liabilities	101,627	131,407
Liabilities	325,220	347,004
Stockholders' equity	804,616	628,588
Noncontrolling interests	296,053	290,377
Total equity	1,100,669	918,965
Total liabilities and equity	1,425,889	1,265,969
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and cash equivalents	0	0	$ 0	$ 0
Marketable securities	0
Accounts receivable, net	(1,850,590)	(1,093,676)
Inventories	0	0
Prepaid expenses and other current assets	(2,879)	0
Deferred income taxes	0	0
Total current assets	(1,853,469)	(1,093,676)
Property, plant and equipment, net	0	0
Equity investments	(6,659,553)	(5,561,703)
Other assets, net	(255,232)	(233,708)
Total assets	(8,768,254)	(6,889,087)
Accounts and notes payable	(1,825,865)	(1,068,835)
Accrued liabilities	(27,604)	(24,841)
Total current liabilities	(1,853,469)	(1,093,676)
Long-term debt	(248,665)	(227,638)
Deferred income taxes	(6,567)	(6,070)
Other liabilities	0	0
Liabilities	(2,108,701)	(1,327,384)
Stockholders' equity	(6,659,553)	(5,561,703)
Noncontrolling interests	0	0
Total equity	(6,659,553)	(5,561,703)
Total liabilities and equity	$ (8,768,254)	$ (6,889,087)

Guarantor Disclosures (Condensed Consolidating Financial Information Statement Of Operations) (Details) - USD ($)
$ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

$ 986,766

$ 1,188,037

$ 1,185,002

$ 1,103,531

$ 1,135,871

$ 1,253,227

$ 998,576

$ 1,027,676

$ 4,463,336

^[1]

$ 4,415,350

^[1]

$ 3,759,484

^[1]

3,278,145

3,098,000

2,658,046

236,188

311,276

353,181

284,546

362,849

361,520

305,971

287,010

1,185,191

1,317,350

1,101,438

225,364

193,359

147,974

181,145

254,028

295,374

229,280

302,387

306,761

266,788

248,055

959,827

1,123,991

953,464

(34,656)

(37,352)

(18,082)

38,270

(2,721)

6,790

963,441

1,083,918

942,172

298,396

398,902

331,747

Net income attributable to noncontrolling interests

665,045

685,016

610,425

19,035

6,493

Net income attributable to Westlake Chemical Corporation

$ 110,969

$ 183,604

$ 205,095

$ 146,342

$ 183,291

$ 167,757

$ 169,443

$ 158,032

646,010

678,523

610,425

Westlake Chemical Corporation [Member]

596,151

601,706

618,649

Condensed Financial Statements, Captions [Line Items]

2,478

2,082

2,128

(2,478)

(2,082)

(2,128)

(42,197)

(39,763)

(18,030)

19,614

21,001

11,798

(25,061)

(20,844)

(8,360)

(7,237)

248

(2,031)

663,834

699,615

616,754

Net income attributable to noncontrolling interests

646,010

678,523

610,425

Net income attributable to Westlake Chemical Corporation

646,010

678,523

610,425

Guarantor Subsidiaries [Member]

596,151

601,706

618,649

Condensed Financial Statements, Captions [Line Items]

3,660,393

3,727,361

3,195,406

2,944,420

3,162,246

2,971,258

715,973

565,115

224,148

167,431

144,987

114,211

548,542

420,128

109,937

(10)

(52)

1,033

(4,921)

(2,438)

549,565

415,197

107,447

288,329

202,501

34,340

314,026

496,244

546,546

Net income attributable to noncontrolling interests

575,262

708,940

619,653

Net income attributable to Westlake Chemical Corporation

575,262

708,940

619,653

Westlake Chemical OpCo LP [Member]

572,731

703,148

629,308

Condensed Financial Statements, Captions [Line Items]

1,007,221

1,749,700

2,127,747

624,339

1,003,888

1,255,140

382,882

745,812

872,607

20,138

26,870

25,451

362,744

718,942

847,156

(2,691)

(10,499)

(8,032)

(63)

3,151

7,701

359,990

711,594

846,825

672

199,388

300,279

Net income attributable to noncontrolling interests

359,318

512,206

546,546

Net income attributable to Westlake Chemical Corporation

359,318

512,206

546,546

Non-Guarantor Subsidiaries [Member]

359,318

512,206

546,546

Condensed Financial Statements, Captions [Line Items]

1,039,165

475,401

48,016

933,007

447,676

43,333

106,158

27,725

4,683

55,139

40,722

6,184

51,019

(12,997)

(1,501)

(521)

(492)

28,449

(8,540)

(2,239)

78,947

(22,029)

(3,740)

16,632

(3,235)

(841)

45,292

15,962

Net income attributable to noncontrolling interests

107,607

(2,832)

(2,899)

19,035

6,493

Net income attributable to Westlake Chemical Corporation

88,572

(9,325)

(2,899)

Condensed Financial Statements, Captions [Line Items]

42,143

(80,407)

(4,506)

Eliminations [Member]

(1,243,443)

(1,537,112)

(1,611,685)

(1,223,621)

(1,515,810)

(1,611,685)

(19,822)

(21,302)

(19,822)

(21,302)

10,763

13,412

8,032

(10,763)

(13,412)

(8,032)

(1,023,152)

(1,211,821)

(1,163,300)

Net income attributable to noncontrolling interests

(1,023,152)

(1,211,821)

(1,163,300)

Net income attributable to Westlake Chemical Corporation

(1,023,152)

(1,211,821)

(1,163,300)

Quarterly Financial Information Disclosure [Abstract]

$ (974,192)

$ (1,134,947)

$ (1,171,348)

[1]	Revenues are attributed to countries based on location of customer.

Guarantor Disclosures (Condensed Consolidating Financial Information Statement Of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	$ 665,045	$ 685,016	$ 610,425
Depreciation and amortization	247,761	210,159	159,267
Deferred income taxes	39,784	58,967	93,732
Net changes in working capital and other	126,246	78,234	(110,695)
Net cash provided by operating activities	1,078,836	1,032,376	752,729
Acquisition of business, net of cash acquired	15,782	(611,087)	(178,309)
Additions to property, plant and equipment	(491,426)	(431,104)	(679,222)
Construction of assets pending sale-leaseback	0	0	(136)
Additions to equity investments	0	0	(23,338)
Proceeds from disposition of assets	49	181	151
Proceeds from sale of equity method investments	27,865	0	0
Proceeds from repayment of loan acquired	0	45,923	0
Proceeds from repayment of loan to affiliate	0	0	167
Proceeds from sales and maturities of securities	48,900	342,045	252,519
Purchase of securities	(605,098)	(117,332)	(367,150)
Settlements of derivative instruments	(2,248)	(1,831)	(6,920)
Net cash used for investing activities	(1,006,176)	(773,205)	(1,002,238)
Intercompany financing	0	0	0
Proceeds from (Repayments of) Intercompany Financing, Subsidiary	0
Net distributions prior to WLKP initial public offering			0
Capitalized debt issuance costs	0	(1,186)	0
Dividends paid	(91,551)	(77,656)	(55,236)
Distribution Made to Limited Partner, Cash Distributions Paid	(14,856)	(2,204)
Net proceeds from issuance of Westlake Chemical Partners LP common units	0	286,088	0
Payments to Acquire Limited Partnership Interests	0	0
Proceeds from exercise of stock options	1,063	5,524	3,437
Proceeds from issuance of notes payable	52,960	0	0
Repayment of notes payable	(73,615)	0	0
Repurchase of common stock for treasury	(162,459)	(52,630)	(32,918)
Windfall tax benefits from share-based payment arrangements	1,646	6,704	5,449
Net cash (used for) provided by financing activities	(286,812)	164,640	(79,268)
Effect of exchange rate changes on cash and cash equivalents	(3,924)	(4,511)	0
Net (decrease) increase in cash and cash equivalents	(218,076)	419,300	(328,777)
Cash and cash equivalents at beginning of the year	880,601	461,301	790,078
Cash and cash equivalents at end of the year	662,525	880,601	461,301
Westlake Chemical Corporation [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	646,010	678,523	610,425
Depreciation and amortization	2,004	1,673	1,459
Deferred income taxes	(285)	(288)	74
Net changes in working capital and other	(660,777)	(706,043)	(622,194)
Net cash provided by operating activities	(13,048)	(26,135)	(10,236)
Acquisition of business, net of cash acquired	0	0	0
Additions to property, plant and equipment	0	0	0
Construction of assets pending sale-leaseback			0
Additions to equity investments			0
Proceeds from disposition of assets	0	0	0
Proceeds from sale of equity method investments	0
Proceeds from repayment of loan acquired		0
Proceeds from repayment of loan to affiliate			0
Proceeds from sales and maturities of securities	48,900	342,045	252,519
Purchase of securities	(556,211)	(117,332)	(367,150)
Settlements of derivative instruments	0	0	0
Net cash used for investing activities	(507,311)	224,713	(114,631)
Intercompany financing	418,844	155,665	(128,798)
Proceeds from (Repayments of) Intercompany Financing, Subsidiary	0
Net distributions prior to WLKP initial public offering		0	0
Capitalized debt issuance costs		(1,186)
Dividends paid	(91,551)	(77,656)	(55,236)
Distribution Made to Limited Partner, Cash Distributions Paid	0	0
Net proceeds from issuance of Westlake Chemical Partners LP common units		0
Payments to Acquire Limited Partnership Interests	0	0
Proceeds from exercise of stock options	1,063	5,524	3,437
Proceeds from issuance of notes payable	0
Repayment of notes payable	0
Repurchase of common stock for treasury	(162,459)	(52,630)	(32,918)
Windfall tax benefits from share-based payment arrangements	1,646	6,704	5,449
Net cash (used for) provided by financing activities	167,543	36,421	(208,066)
Effect of exchange rate changes on cash and cash equivalents	0	0
Net (decrease) increase in cash and cash equivalents	(352,816)	234,999	(332,933)
Cash and cash equivalents at beginning of the year	655,947	420,948	753,881
Cash and cash equivalents at end of the year	303,131	655,947	420,948
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	575,262	708,940	619,653
Depreciation and amortization	124,897	111,389	81,897
Deferred income taxes	33,369	55,344	56,787
Net changes in working capital and other	(368,494)	(1,077,982)	(607,033)
Net cash provided by operating activities	365,034	(202,309)	151,304
Acquisition of business, net of cash acquired	0	0	(178,309)
Additions to property, plant and equipment	(215,405)	(209,111)	(453,538)
Construction of assets pending sale-leaseback			(136)
Additions to equity investments			(23,338)
Proceeds from disposition of assets	18	180	75
Proceeds from sale of equity method investments	27,865
Proceeds from repayment of loan acquired		0
Proceeds from repayment of loan to affiliate			0
Proceeds from sales and maturities of securities	0	0	0
Purchase of securities	(48,887)	0	0
Settlements of derivative instruments	(2,248)	(1,698)	0
Net cash used for investing activities	(238,657)	(210,629)	(655,246)
Intercompany financing	(585,007)	(244,122)	(100,330)
Proceeds from (Repayments of) Intercompany Financing, Subsidiary	135,341
Net distributions prior to WLKP initial public offering		448,101	603,526
Capitalized debt issuance costs		0
Dividends paid	0	151,729	0
Distribution Made to Limited Partner, Cash Distributions Paid	327,060	54,060
Net proceeds from issuance of Westlake Chemical Partners LP common units		0
Payments to Acquire Limited Partnership Interests	0	0
Proceeds from exercise of stock options	0	0	0
Proceeds from issuance of notes payable	0
Repayment of notes payable	0
Repurchase of common stock for treasury	0	0	0
Windfall tax benefits from share-based payment arrangements	0	0	0
Net cash (used for) provided by financing activities	(122,606)	409,768	503,196
Effect of exchange rate changes on cash and cash equivalents	0	0
Net (decrease) increase in cash and cash equivalents	3,771	(3,170)	(746)
Cash and cash equivalents at beginning of the year	3,057	6,227	6,973
Cash and cash equivalents at end of the year	6,828	3,057	6,227
Westlake Chemical OpCo LP [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	359,318	512,206	546,546
Depreciation and amortization	81,210	77,611	73,463
Deferred income taxes	(456)	8,608	37,054
Net changes in working capital and other	19,175	4,879	(54,554)
Net cash provided by operating activities	459,247	603,304	602,509
Acquisition of business, net of cash acquired	0	0	0
Additions to property, plant and equipment	(231,185)	(202,823)	(223,130)
Construction of assets pending sale-leaseback			0
Additions to equity investments			0
Proceeds from disposition of assets	0	0	0
Proceeds from sale of equity method investments	0
Proceeds from repayment of loan acquired		0
Proceeds from repayment of loan to affiliate			0
Proceeds from sales and maturities of securities	0	0	0
Purchase of securities	0	0	0
Settlements of derivative instruments	0	(133)	(6,920)
Net cash used for investing activities	(231,185)	(202,956)	(230,050)
Intercompany financing	156,368	102,702	231,067
Proceeds from (Repayments of) Intercompany Financing, Subsidiary	(135,341)
Net distributions prior to WLKP initial public offering		(448,101)	(603,526)
Capitalized debt issuance costs		0
Dividends paid	0	(151,729)	0
Distribution Made to Limited Partner, Cash Distributions Paid	(352,545)	(57,763)
Net proceeds from issuance of Westlake Chemical Partners LP common units		0
Payments to Acquire Limited Partnership Interests	135,341	286,088
Proceeds from exercise of stock options	0	0	0
Proceeds from issuance of notes payable	0
Repayment of notes payable	0
Repurchase of common stock for treasury	0	0	0
Windfall tax benefits from share-based payment arrangements	0	0	0
Net cash (used for) provided by financing activities	(196,177)	(268,803)	(372,459)
Effect of exchange rate changes on cash and cash equivalents	0	0
Net (decrease) increase in cash and cash equivalents	31,885	131,545	0
Cash and cash equivalents at beginning of the year	131,545	0	0
Cash and cash equivalents at end of the year	163,430	131,545	0
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	107,607	(2,832)	(2,899)
Depreciation and amortization	39,650	19,486	2,448
Deferred income taxes	7,156	(4,697)	(183)
Net changes in working capital and other	113,190	645,559	9,786
Net cash provided by operating activities	267,603	657,516	9,152
Acquisition of business, net of cash acquired	15,782	(611,087)	0
Additions to property, plant and equipment	(44,836)	(19,170)	(2,554)
Construction of assets pending sale-leaseback			0
Additions to equity investments			0
Proceeds from disposition of assets	31	1	76
Proceeds from sale of equity method investments	0
Proceeds from repayment of loan acquired		45,923
Proceeds from repayment of loan to affiliate			167
Proceeds from sales and maturities of securities	0	0	0
Purchase of securities	0	0	0
Settlements of derivative instruments	0	0	0
Net cash used for investing activities	(29,023)	(584,333)	(2,311)
Intercompany financing	9,795	(14,245)	(1,939)
Proceeds from (Repayments of) Intercompany Financing, Subsidiary	0
Net distributions prior to WLKP initial public offering		0	0
Capitalized debt issuance costs		0
Dividends paid	0	0	0
Distribution Made to Limited Partner, Cash Distributions Paid	10,629	1,499
Net proceeds from issuance of Westlake Chemical Partners LP common units		286,088
Payments to Acquire Limited Partnership Interests	(135,341)	(286,088)
Proceeds from exercise of stock options	0	0	0
Proceeds from issuance of notes payable	52,960
Repayment of notes payable	(73,615)
Repurchase of common stock for treasury	0	0	0
Windfall tax benefits from share-based payment arrangements	0	0	0
Net cash (used for) provided by financing activities	(135,572)	(12,746)	(1,939)
Effect of exchange rate changes on cash and cash equivalents	(3,924)	(4,511)
Net (decrease) increase in cash and cash equivalents	99,084	55,926	4,902
Cash and cash equivalents at beginning of the year	90,052	34,126	29,224
Cash and cash equivalents at end of the year	189,136	90,052	34,126
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net income (loss)	(1,023,152)	(1,211,821)	(1,163,300)
Depreciation and amortization	0	0	0
Deferred income taxes	0	0	0
Net changes in working capital and other	1,023,152	1,211,821	1,163,300
Net cash provided by operating activities	0	0	0
Acquisition of business, net of cash acquired	0	0	0
Additions to property, plant and equipment	0	0	0
Construction of assets pending sale-leaseback			0
Additions to equity investments			0
Proceeds from disposition of assets	0	0	0
Proceeds from sale of equity method investments	0
Proceeds from repayment of loan acquired		0
Proceeds from repayment of loan to affiliate			0
Proceeds from sales and maturities of securities	0	0	0
Purchase of securities	0	0	0
Settlements of derivative instruments	0	0	0
Net cash used for investing activities	0	0	0
Intercompany financing			0
Net distributions prior to WLKP initial public offering		0	0
Capitalized debt issuance costs		0
Dividends paid	0	0	0
Distribution Made to Limited Partner, Cash Distributions Paid	0	0
Net proceeds from issuance of Westlake Chemical Partners LP common units		0
Payments to Acquire Limited Partnership Interests	0	0
Proceeds from exercise of stock options	0	0	0
Proceeds from issuance of notes payable	0
Repayment of notes payable	0
Repurchase of common stock for treasury	0	0	0
Windfall tax benefits from share-based payment arrangements	0	0	0
Net cash (used for) provided by financing activities	0	0	0
Effect of exchange rate changes on cash and cash equivalents	0	0
Net (decrease) increase in cash and cash equivalents	0	0	0
Cash and cash equivalents at beginning of the year	0	0	0
Cash and cash equivalents at end of the year	$ 0	$ 0	$ 0

Quarterly Financial Information (Summary Of Quarterly Financial Information) (Details) - USD ($)
$ / shares in Units, $ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

$ 986,766

$ 1,188,037

$ 1,185,002

$ 1,103,531

$ 1,135,871

$ 1,253,227

$ 998,576

$ 1,027,676

$ 4,463,336

^[1]

$ 4,415,350

^[1]

$ 3,759,484

^[1]

236,188

311,276

353,181

284,546

362,849

361,520

305,971

287,010

1,185,191

1,317,350

1,101,438

181,145

254,028

295,374

229,280

302,387

306,761

266,788

248,055

959,827

1,123,991

953,464