0001262823-24-000025 | 10-Q | XBRL Viewer

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Consolidated Balance Sheets (Unaudited) (Parentheticals) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Preferred stock, par value, in dollars per share	$ 0.01	$ 0.01
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, shares outstanding	0	0
Common stock, par value, in dollars per share	$ 0.01	$ 0.01
Common stock, shares authorized	300,000,000	300,000,000
Common Stock
Common Stock, Shares, Issued	134,651,380	134,651,380
Common Stock, Held in Treasury
Treasury Stock, Common, Shares	6,082,171	6,439,289

Accounts Payable

3 Months Ended

Mar. 31, 2024

Accounts Payable [Abstract]

Accounts Payable

Accounts payable consist of the following:


	March 31, 2024		December 31, 2023
Accounts payable—third parties	$	871	$	849
Accounts payable to related parties	12		15
Notes payable	8		13
Accounts payable	$	891	$	877

Segment Information (Reconciliation of Total Segment Income from Operations to Consolidated Income before Income Taxes) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting [Abstract]
Income from operations	$ 223	$ 536
Interest expense	(40)	(42)
Other income, net	50	22
Income before income taxes	$ 233	$ 516

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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+ Details

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References + Details

Earnings and Dividends per Share

3 Months Ended

Mar. 31, 2024

Earnings and Dividends Per Share [Abstract]

Earnings and Dividends per Share

Earnings per Share

The Company has unvested 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 each period. Diluted earnings per share include the effects of certain stock options and performance stock units.


	Three Months Ended March 31,
		2024		2023
Net income attributable to Westlake Corporation		$	174	$	394
Less:
Net income attributable to participating securities		(1)		(2)
Net income attributable to common shareholders		$	173	$	392

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


	Three Months Ended March 31,
		2024		2023
Weighted average common shares—basic		128,359,983		127,548,287
Plus incremental shares from:
Assumed exercise of options and vesting of performance stock units		660,387		911,081
Weighted average common shares—diluted		129,020,370		128,459,368

Earnings per common share attributable to Westlake Corporation:
Basic		$	1.35	$	3.07
Diluted		$	1.34	$	3.05

Excluded from the computation of diluted earnings per share are options to purchase 260,722 and 307,411 shares of common stock for the three months ended March 31, 2024 and 2023. These options were outstanding during the periods reported but were excluded because the effect of including them would have been antidilutive.

Dividends per Share

Dividends declared per common share for the three months ended March 31, 2024 and 2023 were as follows:


	Three Months Ended March 31,
		2024		2023
Dividends per common share		$	0.5000	$	0.3570

Commitments and Contingencies (Additional Information) (Detail) - USD ($) $ in Millions					1 Months Ended					3 Months Ended
	Oct. 16, 2023	Sep. 12, 2023	May 22, 2019	Jun. 18, 2018	Oct. 31, 2023	Sep. 30, 2023	Apr. 30, 2022	Mar. 31, 2019	May 31, 2017	Mar. 31, 2024	Dec. 31, 2023
Environmental Loss Contingencies [Line Items]
Environmental loss contingency accrual										$ 57	$ 58
Avient
Environmental Loss Contingencies [Line Items]
Site contingency, percentage of cost potentially of other responsible parties			100.00%
Minimum
Environmental Loss Contingencies [Line Items]
Environmental exit costs, reasonably possible additional loss										125
Maximum
Environmental Loss Contingencies [Line Items]
Environmental exit costs, reasonably possible additional loss										$ 200
Groundwater Monitoring
Environmental Loss Contingencies [Line Items]
Environmental exit costs, anticipated cost						$ 14
EPA \| Operation and Maintenance \| Minimum
Environmental Loss Contingencies [Line Items]
Environmental exit costs, anticipated cost				$ 1
EPA \| Operation and Maintenance \| Maximum
Environmental Loss Contingencies [Line Items]
Environmental exit costs, anticipated cost				3
EPA \| Cost of Implementation
Environmental Loss Contingencies [Line Items]
Environmental exit costs, anticipated cost				$ 107
Pending Litigation \| Avient
Environmental Loss Contingencies [Line Items]
Damages sought							$ 22		$ 11
Site contingency, percentage of cost potentially of other responsible parties										100.00%
Antitrust Proceedings \| Direct Purchasers \| Settled Litigation
Environmental Loss Contingencies [Line Items]
Damages sought								$ 861
Litigation settlement, amount awarded to other party	$ 19
Antitrust Proceedings \| Indirect Purchasers \| Settled Litigation
Environmental Loss Contingencies [Line Items]
Damages sought								$ 500
Ethylene Antitrust Litigation Proceedings \| Pending Litigation
Environmental Loss Contingencies [Line Items]
Damages sought					$ 1,026
Triad Hunter Proceedings \| Settled Litigation
Environmental Loss Contingencies [Line Items]
Litigation settlement, amount awarded to other party		$ 70
Petro 2 Flash Fire And EDC Storage Tank Explosion
Environmental Loss Contingencies [Line Items]
Litigation settlement, amount awarded to other party										$ 150
Environmental loss contingency accrual										151
Loss Contingency, Damages Awarded, Value										382
Loss Contingency, Receivable										13
Petro 2 Flash Fire And EDC Storage Tank Explosion \| Insurance Claims
Environmental Loss Contingencies [Line Items]
Damages sought										$ 150

Segment Information (Total Assets) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 20,960	$ 21,035
Operating Segments \| Performance and Essential Materials Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	13,430	13,538
Operating Segments \| Housing and Infrastructure Products Segment
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	5,078	4,888
Corporate and other
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 2,452	$ 2,609

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details

Inventories (Tables)

3 Months Ended

Mar. 31, 2024

Inventory Disclosure [Abstract]

Schedule Of Inventory

Inventories consist of the following:


	March 31, 2024		December 31, 2023
Finished products	$	1,055	$	989
Feedstock, additives, chemicals and other raw materials	372		401
Materials and supplies	234		232
Inventories	$	1,661	$	1,622

Westlake Chemical Partners LP (Details) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
	Oct. 04, 2018	Mar. 31, 2024	Jun. 30, 2015
Related Party Transaction [Line Items]
Partners' capital, sold in public offering (in shares)			12,937,500
Partners' Units, Maximum Aggregate Offering Amount, ATM	$ 50
Subsidiary of Common Parent \| Limited Partner \| Westlake Chemical OpCo LP
Related Party Transaction [Line Items]
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest		22.80%
Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest		77.20%
Subsidiary of Common Parent \| Limited Partner \| Westlake Chemical Partners LP
Related Party Transaction [Line Items]
Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest		40.10%
Ownership interest (in shares)		14,122,230

Earnings and Dividends per Share (Tables)

3 Months Ended

Mar. 31, 2024

Earnings and Dividends Per Share [Abstract]

Schedule Of Net Income Attributable To Common Stockholders

Diluted earnings per share include the effects of certain stock options and performance stock units.


	Three Months Ended March 31,
		2024		2023
Net income attributable to Westlake Corporation		$	174	$	394
Less:
Net income attributable to participating securities		(1)		(2)
Net income attributable to common shareholders		$	173	$	392

Reconciliation Of Denominator For Basic And Diluted Earnings Per Share

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


	Three Months Ended March 31,
		2024		2023
Weighted average common shares—basic		128,359,983		127,548,287
Plus incremental shares from:
Assumed exercise of options and vesting of performance stock units		660,387		911,081
Weighted average common shares—diluted		129,020,370		128,459,368

Earnings per common share attributable to Westlake Corporation:
Basic		$	1.35	$	3.07
Diluted		$	1.34	$	3.05

Dividends Per Share

Dividends per Share

Dividends declared per common share for the three months ended March 31, 2024 and 2023 were as follows:


	Three Months Ended March 31,
		2024		2023
Dividends per common share		$	0.5000	$	0.3570

Accumulated Other Comprehensive Income (Loss) (Tables)

3 Months Ended

Mar. 31, 2024

Equity [Abstract]

Schedule of Accumulated Other Comprehensive Income (Loss)

Changes in accumulated other comprehensive income (loss) by component for the three months ended March 31, 2024 and 2023 were as follows:


	Pension and Other Post-Retirement Benefits Liability, Net of Tax		Cumulative Foreign Currency Exchange, Net of Tax		Other, Net of Tax		Total
Balances at December 31, 2023	$	4	$	(102)	$	—	$	(98)
Net other comprehensive income (loss) attributable to Westlake Corporation	1		(35)		—		(34)
Balances at March 31, 2024	$	5	$	(137)	$	—	$	(132)

Balances at December 31, 2022	$	52	$	(141)	$	—	$	(89)
Net other comprehensive income (loss) attributable to Westlake Corporation	—		23		(1)		22
Balances at March 31, 2023	$	52	$	(118)	$	(1)	$	(67)

Goodwill (Details) $ in Millions	3 Months Ended
Goodwill (Details) $ in Millions	Mar. 31, 2024 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 2,041
Effects of changes in foreign exchange rates	(4)
Ending Balance	2,037
Performance and Essential Materials Segment
Goodwill [Roll Forward]
Beginning Balance	897
Effects of changes in foreign exchange rates	(2)
Ending Balance	895
Housing and Infrastructure Products Segment
Goodwill [Roll Forward]
Beginning Balance	1,144
Effects of changes in foreign exchange rates	(2)
Ending Balance	$ 1,142

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References + Details

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The effective income tax rate was 20.6% for the three months ended March 31, 2024 as compared to 21.1% for the three months ended March 31, 2023. The effective income tax rate for the three months ended March 31, 2024 was below the statutory rate of 21.0% primarily due to U.S. federal research and development credits available to the Company, partially offset by state and foreign taxes. The effective income tax rate for the three months ended March 31, 2023 was above the statutory rate of 21.0% primarily due to state and foreign taxes partially offset by U.S. federal research and development credits available to the Company. On October 8, 2021, the Organization for Economic Co-operation and Development (the "OECD")/G20 Inclusive Framework on Base Erosion and Profit Shifting released a statement indicating that its members had agreed to a Two – Pillar Solution to Address the Tax Challenges Arising from the Digitalisation of the Economy. Pillar One aims to reallocate a taxpayer's residual profits to the market jurisdictions with which the taxpayer has a nexus. Pillar Two aims to establish a minimum global tax rate of 15%, assessed through a top-up tax imposed on a country-by-country basis. Pillar One targets multinational companies with global annual revenue exceeding €20 billion and profit-to-revenue ratio of more than 10%. Based on the current threshold requirements, the Company does not expect to be subject to Pillar One. On December 20, 2021, the OECD released the Pillar Two model rules providing a framework for implementing a 15% minimum tax, also referred to as the Global Anti-Base Erosion ("GloBE") rules, on earnings of multinational companies with consolidated annual revenue exceeding €750 million. On December 12, 2022, European Union (EU) member states agreed to adopt the 15% minimum tax under the Pillar Two model rules to be enacted into the member states' domestic tax laws by December 31, 2023, with an effective date beginning in 2024. As of March 31, 2024, a handful of EU member states have yet to comply. Outside of the EU, several other jurisdictions that the Company operates in have enacted legislation consistent with the GloBE rules, while other foreign countries continue to debate adoption and timing to adopt. The Company's global footprint includes operations within the EU, as well as other non-EU jurisdictions that have enacted GloBE related legislation, such as Japan, South Korea, Vietnam, the UK and Switzerland. At this time, the Company anticipates qualifying for at least one safe harbor in the majority of jurisdictions in which it operates. For those jurisdictions where a safe harbor was not met, the impact is anticipated to be immaterial. The Company will continue to closely monitor Pillar Two developments and evaluate the potential impact to the Company as more foreign countries enact legislation, and as new information and guidance becomes available. The impacts of Pillar Two are recorded in 2024, the first year in which the rules take effect.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

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-Topic 946
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-Paragraph 14
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-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
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+ Details

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Net sales	$ 2,975	$ 3,356
Cost of sales	2,509	2,564
Gross profit	466	792
Selling, general and administrative expenses	209	222
Amortization of intangibles	30	31
Restructuring, transaction and integration-related costs	4	3
Income from operations	223	536
Other income (expense)
Interest expense	(40)	(42)
Other income, net	50	22
Income before income taxes	233	516
Provision for income taxes	48	109
Net income	185	407
Net income attributable to noncontrolling interests	11	13
Net income attributable to Westlake Corporation	$ 174	$ 394
Earnings per common share attributable to Westlake Corporation:
Basic (in dollars per share)	$ 1.35	$ 3.07
Diluted (in dollars per share)	$ 1.34	$ 3.05
Weighted average common shares outstanding:
Basic (in shares)	128,359,983	127,548,287
Diluted (in shares)	129,020,370	128,459,368

Accounts Payable (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Accounts and Notes Payable [Line Items]
Notes payable	$ 8	$ 13
Accounts payable	891	877
Nonrelated Party
Accounts and Notes Payable [Line Items]
Accounts payable—third parties	871	849
Related Party
Accounts and Notes Payable [Line Items]
Accounts payable—third parties	$ 12	$ 15

Supplemental Information (Equity Method Investments) (Details) - LACC, LLC $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	50.00%
Equity Method Investments Activity [Roll Forward]
Investment, Beginning Balance	$ 1,047
Depreciation and amortization	(12)
Investment, Ending Balance	$ 1,035

- Definition

Fair value of investment in security owned.

+ References

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+ Details

Long-Term Debt

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Long-Term Debt

Long-term debt consists of the following:


	March 31, 2024		December 31, 2023


0.875% senior notes due 2024	$	300		$	300
3.60% senior notes due 2026	750			750
Loan related to tax-exempt waste disposal revenue bonds due 2027	11			11
1.625% €700 million senior notes due 2029	756			773
3.375% senior notes due 2030	300			300
3.50% senior notes due 2032	250			250
2.875% senior notes due 2041	350			350
5.00% senior notes due 2046	700			700
4.375% senior notes due 2047	500			500
3.125% senior notes due 2051	600			600
3.375% senior notes due 2061	450			450
Term loans due 2026	12			13
Total long-term debt, principal amount	4,979			4,997
Less:
Unamortized discount and debt issuance costs	89			91
Long-term debt, carrying value	4,890			4,906
Less current portion:
0.875% senior notes due 2024	300			299
Long-term debt, carrying value, net of current portion	$	4,590		$	4,607

Unamortized debt issuance costs on long-term debt were $35 and $36 at March 31, 2024 and December 31, 2023, respectively. As of March 31, 2024, the Company was in compliance with all of its long-term debt covenants.

Credit Agreement

On June 9, 2022, the Company entered into a new $1,500 revolving credit facility that is scheduled to mature on June 9, 2027 (the "Credit Agreement") and, in connection therewith, terminated the Company's then existing revolving credit agreement. The Credit Agreement bears interest at either (a) Adjusted Term Secured Overnight Financing Rate (as defined in the Credit Agreement) plus a margin ranging from 1.00% to 1.625% per annum or (b) Alternate Base Rate (as defined in the Credit Agreement) plus a margin ranging from 0.00% to 0.625% per annum, in each case depending on the credit rating of the Company. The Credit Agreement contains certain affirmative and negative covenants, including a quarterly total leverage ratio financial maintenance covenant. As of March 31, 2024, the Company was in compliance with the total leverage ratio financial maintenance covenant. The Credit Agreement also contains certain events of default and, if and for so long as certain events of default have occurred and are continuing, any overdue amounts outstanding under the Credit Agreement will accrue interest at an increased rate, the lenders can terminate their commitments to lend thereunder and payments of any outstanding amounts thereunder could be accelerated by the lenders. None of the Company's subsidiaries are required to guarantee the obligations of the Company under the Credit Agreement.

The Credit Agreement includes a $150 sub-limit for letters of credit, and any outstanding letters of credit will be deducted from availability under the facility. The Credit Agreement also provides for a discretionary $50 commitment for swingline loans to be provided on a same-day basis. The Company may also increase the size of the facility, in increments of at least $25, up to a maximum of $500, subject to certain conditions and if certain lenders agree to commit to such an increase.

As of March 31, 2024, the Company had no borrowings and no letters of credit outstanding, and had borrowing availability of $1,500, under the Credit Agreement.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Current	$ 544	$ 360
Restricted Cash and Cash Equivalents	$ 16	$ 15

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash flows from operating activities
Net income	$ 185	$ 407
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation and amortization	273	267
Stock-based compensation expense	9	9
Loss from disposition and write-off of property, plant and equipment	5	6
Deferred income taxes	(22)	(16)
Other gains, net	(3)	(4)
Changes in operating assets and liabilities, net of effect of business acquisitions
Accounts receivable	(97)	(15)
Inventories	(47)	34
Prepaid expenses and other current assets	15	6
Accounts payable	63	(20)
Accrued and other liabilities	(111)	(69)
Other, net	(101)	(93)
Net cash provided by operating activities	169	512
Cash flows from investing activities
Additions to investments in unconsolidated subsidiaries	(1)	(1)
Additions to property, plant and equipment	(272)	(267)
Other, net	1	5
Net cash used for investing activities	(272)	(263)
Cash flows from financing activities
Distributions to noncontrolling interests	(10)	(10)
Dividends paid	(65)	(47)
Proceeds from exercise of stock options	7	5
Repurchase of common stock for treasury	0	(22)
Other, net	(6)	(1)
Net cash used for financing activities	(74)	(75)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(18)	9
Net increase (decrease) in cash, cash equivalents and restricted cash	(195)	183
Cash, cash equivalents and restricted cash at beginning of period	3,319	2,246
Cash, cash equivalents and restricted cash at end of period	$ 3,124	$ 2,429

Income Taxes (Details)	3 Months Ended
Income Taxes (Details)	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Effective income tax rate	20.60%	21.10%
U.S. federal statutory income tax rate	21.00%	21.00%

Segment Information

3 Months Ended

Mar. 31, 2024

Segment Reporting [Abstract]

Segment Information

The Company operates in two principal operating segments: Performance and Essential Materials and Housing and Infrastructure Products. These segments are strategic business units that offer a variety of different materials and products. The Company manages each segment separately as each business requires different technology and marketing strategies.


	Three Months Ended March 31,
		2024		2023
Net external sales
Performance and Essential Materials
Performance Materials		$	1,164	$	1,282
Essential Materials		767		1,067
Total Performance and Essential Materials		1,931		2,349
Housing and Infrastructure Products
Housing Products		879		818
Infrastructure Products		165		189
Total Housing and Infrastructure Products		1,044		1,007
		$	2,975	$	3,356

Intersegment sales
Performance and Essential Materials		$	111	$	111
Housing and Infrastructure Products		—		—
		$	111	$	111

Income (loss) from operations
Performance and Essential Materials		$	22	$	403
Housing and Infrastructure Products		210		143
Corporate and other		(9)		(10)
		$	223	$	536

Depreciation and amortization
Performance and Essential Materials		$	220	$	210
Housing and Infrastructure Products		50		55
Corporate and other		3		2
		$	273	$	267

Other income, net
Performance and Essential Materials		$	11	$	2
Housing and Infrastructure Products		4		7
Corporate and other		35		13
		$	50	$	22

Provision for (benefit from) income taxes
Performance and Essential Materials		$	(11)	$	67
Housing and Infrastructure Products		56		37
Corporate and other		3		5
		$	48	$	109


	Three Months Ended March 31,
		2024		2023
Capital expenditures
Performance and Essential Materials		$	230	$	226
Housing and Infrastructure Products		37		38
Corporate and other		5		3
		$	272	$	267

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


	Three Months Ended March 31,
		2024		2023
Income from operations		$	223	$	536
Interest expense		(40)		(42)
Other income, net		50		22
Income before income taxes		$	233	$	516


	March 31, 2024		December 31, 2023
Total assets
Performance and Essential Materials	$	13,430	$	13,538
Housing and Infrastructure Products	5,078		4,888
Corporate and other	2,452		2,609
	$	20,960	$	21,035

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-22

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-15

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-31

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-42

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 40
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-40

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//280/tableOfContent

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 26
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-26

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-34

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 41
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-41

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-21

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-32

+ Details

Accounts Payable (Tables)

3 Months Ended

Mar. 31, 2024

Accounts Payable [Abstract]

Schedule of Accounts Payable

Accounts payable consist of the following:


	March 31, 2024		December 31, 2023
Accounts payable—third parties	$	871	$	849
Accounts payable to related parties	12		15
Notes payable	8		13
Accounts payable	$	891	$	877

Supplemental Information

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Supplemental Information

Equity Method Investments

LACC, LLC Joint Venture

As of March 31, 2024, the Company owned an aggregate 50% membership interest in LACC, LLC ("LACC"). The Company accounts for its investment in LACC under the equity method of accounting and the change for the three months ended March 31, 2024 was as follows:


	Investment in LACC





Balance at December 31, 2023	$	1,047


Depreciation and amortization	(12)

Balance at March 31, 2024	$	1,035

Other Assets, Net

Other assets, net were $694 and $651 at March 31, 2024 and December 31, 2023, respectively. Deferred turnaround costs, net of accumulated amortization, included in other assets, net were $420 and $391 at March 31, 2024 and December 31, 2023, respectively.

Accrued and Other Liabilities

Accrued and other liabilities were $1,464 and $1,614 at March 31, 2024 and December 31, 2023, respectively. Accrued rebates, accrued litigation reserves and accrued income taxes, which are components of accrued and other liabilities, were $158, $267, and $136, respectively, at March 31, 2024 and $217, $297, and $121, respectively, at December 31, 2023. No other component of accrued and other liabilities was more than five percent of total current liabilities. Accrued liabilities with related parties were $37 and $41 at March 31, 2024 and December 31, 2023, respectively.

Non-cash Investing Activities

Capital expenditure related liabilities, included in accounts payable and accrued and other liabilities, were $112 and $111 at March 31, 2024 and March 31, 2023, respectively.

A non-cash charge of $16 related to asset retirement obligations was recognized in the three months ended March 31, 2024.

Other Income, Net

The other income, net of $50 for the three months ended March 31, 2024 included interest income of $40 and other income, net of $22 for the three months ended March 31, 2023 included interest income of $18.

Supplemental Cash Flow Information


	Three Months Ended March 31,
	2024		2023
Cash paid for:
Interest, net of interest capitalized	$	52	$	54
Income taxes	46		23
Operating lease information:
Right-of-use assets obtained in exchange for operating lease obligations	$	44	$	56

Basis of Financial Statements	3 Months Ended
Basis of Financial Statements	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Financial Statements	Basis of Financial Statements The accompanying unaudited consolidated interim financial statements were prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the "SEC") for interim periods. Accordingly, certain information and footnotes required for complete financial statements under generally accepted accounting principles in the United States ("U.S. GAAP") have not been included. These interim consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto of Westlake Corporation (the "Company"), included in the annual report on Form 10-K for the fiscal year ended December 31, 2023 (the "2023 Form 10-K"), filed with the SEC on February 22, 2024. These consolidated financial statements have been prepared in conformity with the accounting principles and practices as disclosed in the notes to the consolidated financial statements of the Company for the fiscal year ended December 31, 2023. The Company operates as an integrated global manufacturer and marketer of performance and essential materials and housing and infrastructure products. These products include some of the most widely used materials in the world, which are fundamental to many diverse consumer and industrial markets, including residential construction, flexible and rigid packaging, automotive products, healthcare products, materials used in turbines to generate wind energy, water treatment, coatings 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 throughout North America, Europe and Asia. In the opinion of the Company's management, the accompanying unaudited consolidated interim financial statements reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Company's financial position as of March 31, 2024, its results of operations for the three months ended March 31, 2024 and 2023, and the changes in its cash position for the three months ended March 31, 2024 and 2023. Results of operations and changes in cash position for the interim periods presented are not necessarily indicative of the results that will be realized for the fiscal year ending December 31, 2024 or any other interim period. The preparation of consolidated financial statements in conformity with U.S. GAAP 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. Recently Issued Accounting Pronouncements Income Taxes (Topic 740): Improvements to Income Tax Disclosures (ASU No.2023-09) In December 2023, the Financial Accounting Standards Board ("FASB") issued accounting standards update No. 2023-09 to enhance the transparency and decision-usefulness of income tax disclosures and to provide information to better assess how an entity's operations and related tax risks and tax planning and operational opportunities affect its tax rate and prospects for future cash flows. For public business entities, the amendments in this update are effective for annual periods beginning after December 15, 2024. The Company is in the process of evaluating the impact of this standard on the Company's disclosures in the financial statements. Business Combinations—Joint Venture Formations (Subtopic 805-60): Recognition and Initial Measurement (ASU 2023-05) In August 2023, the FASB issued accounting standards update No. 2023-05 to address the accounting for contributions made to a joint venture, upon formation, in a joint venture's financial statements, and to (1) provide decision-useful information to investors and other allocators of capital (collectively, investors) in a joint venture's financial statements and (2) reduce diversity in practice. Under the ASU, upon formation, a joint venture should recognize and initially measure its assets and liabilities at fair value (with exceptions to fair value measurement that are consistent with guidance for business combinations). The amendments in this update become effective for all joint venture formations with a formation date on or after January 1, 2025. Additionally, a joint venture that was formed before January 1, 2025 may elect to apply the amendments retrospectively if it has sufficient information. Early adoption is permitted in any interim or annual period in which financial statements have not yet been issued (or made available for issuance), either prospectively or retrospectively. The Company does not expect that this accounting standard will have a material impact, upon adoption, on the Company's consolidated financial position, results of operations and cash flows. Recently Adopted Accounting Standards Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (ASU 2023-07) In November 2023, the FASB issued accounting standards update No. 2023-07 to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. The update requires public entities to disclose, on an annual and interim basis, significant segment expenses that are regularly provided to the chief operating decision maker (CODM), the title and position of the CODM and an explanation of how the CODM uses the reported measure(s) of segment profit or loss in assessing segment performance and deciding how to allocate resources. The amendments in this update are effective for public entities in fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, and are to be applied retrospectively to all prior periods presented in the financial statements. Early adoption is permitted. The Company adopted this accounting standard effective January 1, 2024, and the adoption will result in additional segment disclosures in the Company's annual consolidated financial statements for the year ending December 31, 2024 and the interim periods thereafter. Leases (Topic 842): Common Control Arrangements (ASU 2023-01) In March 2023, the FASB issued accounting standards update No. 2023-01 to amend certain provisions of ASC 842 that apply to arrangements between related parties under common control. The update requires all companies to amortize leasehold improvements associated with common control leases over the asset's useful life to the common control group regardless of the lease term. The amendment in this update is effective for all entities in fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early application is permitted. The Company adopted this accounting standard effective January 1, 2024, and the adoption did not have a material impact on the Company's consolidated financial position, results of operations and cash flows.

Accumulated Other Comprehensive Income (Loss)

3 Months Ended

Mar. 31, 2024

Equity [Abstract]

Accumulated Other Comprehensive Income (Loss)

Changes in accumulated other comprehensive income (loss) by component for the three months ended March 31, 2024 and 2023 were as follows:


	Pension and Other Post-Retirement Benefits Liability, Net of Tax		Cumulative Foreign Currency Exchange, Net of Tax		Other, Net of Tax		Total
Balances at December 31, 2023	$	4	$	(102)	$	—	$	(98)
Net other comprehensive income (loss) attributable to Westlake Corporation	1		(35)		—		(34)
Balances at March 31, 2024	$	5	$	(137)	$	—	$	(132)

Balances at December 31, 2022	$	52	$	(141)	$	—	$	(89)
Net other comprehensive income (loss) attributable to Westlake Corporation	—		23		(1)		22
Balances at March 31, 2023	$	52	$	(118)	$	(1)	$	(67)

Westlake Chemical Partners LP	3 Months Ended
Westlake Chemical Partners LP	Mar. 31, 2024
Partners' Capital [Abstract]
Westlake Chemical Partners LP	Westlake Chemical Partners LP In 2014, the Company formed Westlake Chemical Partners LP ("Westlake Partners") to operate, acquire and develop ethylene production facilities and related assets. Also in 2014, Westlake Partners completed its initial public offering of 12,937,500 common units. As of March 31, 2024, Westlake Partners had a 22.8% limited partner interest in Westlake Chemical OpCo LP ("OpCo"), and the Company retained a 77.2% limited partner interest in OpCo and a significant interest in Westlake Partners through the Company's ownership of Westlake Partners' general partner, 40.1% of the limited partner interests (consisting of 14,122,230 common units) and incentive distribution rights. On October 4, 2018, Westlake Partners and Westlake Chemical Partners GP LLC, the general partner of Westlake Partners, entered into an Equity Distribution Agreement with UBS Securities LLC, Barclays Capital Inc., Citigroup Global Markets Inc., Deutsche Bank Securities Inc., RBC Capital Markets, LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and Wells Fargo Securities, LLC to offer and sell Westlake Partners' common units, from time to time, up to an aggregate offering amount of $50. This Equity Distribution Agreement was amended on February 28, 2020 to reference a new shelf registration and subsequent renewals thereof for utilization under this agreement. No common units were issued under this program as of March 31, 2024.

Segment Information (Additional Information) (Detail)	3 Months Ended
Segment Information (Additional Information) (Detail)	Mar. 31, 2024 Segment
Segment Reporting [Abstract]
Number of segments	2

Inventories

3 Months Ended

Mar. 31, 2024

Inventory Disclosure [Abstract]

Inventories

Inventories consist of the following:


	March 31, 2024		December 31, 2023
Finished products	$	1,055	$	989
Feedstock, additives, chemicals and other raw materials	372		401
Materials and supplies	234		232
Inventories	$	1,661	$	1,622

Long-Term Debt (Credit Agreement) (Details) - Credit Agreement - USD ($) $ in Millions	Jun. 09, 2022	Mar. 31, 2024
Line of Credit \| Minimum
Debt Instrument [Line Items]
Line of credit permitted increase	$ 25
Line of Credit \| Maximum
Debt Instrument [Line Items]
Line of credit permitted increase	500
Revolving Credit Facility
Debt Instrument [Line Items]
Remaining borrowing capacity		$ 1,500
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1,500
Borrowing outstanding		$ 0
Revolving Credit Facility \| Line of Credit \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| Minimum
Debt Instrument [Line Items]
Spread on variable rate	1.00%
Revolving Credit Facility \| Line of Credit \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate \| Maximum
Debt Instrument [Line Items]
Spread on variable rate	1.625%
Revolving Credit Facility \| Line of Credit \| Alternate Base Rate \| Minimum
Debt Instrument [Line Items]
Spread on variable rate	0.00%
Revolving Credit Facility \| Line of Credit \| Alternate Base Rate \| Maximum
Debt Instrument [Line Items]
Spread on variable rate	0.625%
Letter of Credit \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 150
Swingline Loan \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 50

Segment Information (Segment Reporting Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Net sales	$ 2,975	$ 3,356
Income (loss) from operations	223	536
Depreciation and amortization	273	267
Other income, net	50	22
Provision for (benefit from) income taxes	48	109
Capital expenditures	272	267
Operating Segments \| Performance and Essential Materials Segment
Segment Reporting Information [Line Items]
Net sales	1,931	2,349
Income (loss) from operations	22	403
Depreciation and amortization	220	210
Other income, net	11	2
Provision for (benefit from) income taxes	(11)	67
Capital expenditures	230	226
Operating Segments \| Performance and Essential Materials Segment \| Performance Materials
Segment Reporting Information [Line Items]
Net sales	1,164	1,282
Operating Segments \| Performance and Essential Materials Segment \| Essential Materials
Segment Reporting Information [Line Items]
Net sales	767	1,067
Operating Segments \| Housing and Infrastructure Products Segment
Segment Reporting Information [Line Items]
Net sales	1,044	1,007
Income (loss) from operations	210	143
Depreciation and amortization	50	55
Other income, net	4	7
Provision for (benefit from) income taxes	56	37
Capital expenditures	37	38
Operating Segments \| Housing and Infrastructure Products Segment \| Housing Products
Segment Reporting Information [Line Items]
Net sales	879	818
Operating Segments \| Housing and Infrastructure Products Segment \| Infrastructure Products
Segment Reporting Information [Line Items]
Net sales	165	189
Intersegment sales
Segment Reporting Information [Line Items]
Net sales	111	111
Intersegment sales \| Performance and Essential Materials Segment
Segment Reporting Information [Line Items]
Net sales	111	111
Intersegment sales \| Housing and Infrastructure Products Segment
Segment Reporting Information [Line Items]
Net sales	0	0
Corporate and other
Segment Reporting Information [Line Items]
Income (loss) from operations	(9)	(10)
Depreciation and amortization	3	2
Other income, net	35	13
Provision for (benefit from) income taxes	3	5
Capital expenditures	$ 5	$ 3

Accounts Receivable (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit losses	$ (24)	$ (27)
Accounts receivable from trade customers, net	1,516	1,393
Federal and state taxes	59	65
Other	116	143
Accounts receivable, net	1,691	1,601
Nonrelated Party
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade customers	1,537	1,413
Related Party
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade customers	$ 3	$ 7

Fair Value Measurements (Summary of Carrying and Fair Values of Long Term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Carrying Value	$ 4,890	$ 4,906
Fair Value	$ 4,180	$ 4,236

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details

Goodwill (Tables)

3 Months Ended

Mar. 31, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Goodwill

The carrying amounts and changes in the carrying amount of goodwill for the three months ended March 31, 2024 were as follows:


	Performance and Essential Materials Segment		Housing and Infrastructure Products Segment		Total
Balances at December 31, 2023	$	897	$	1,144	$	2,041



Effects of changes in foreign exchange rates	(2)		(2)		(4)
Balances at March 31, 2024	$	895	$	1,142	$	2,037

- Definition

Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 350
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 24
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482548/350-20-55-24

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 350
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-Name Accounting Standards Codification
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net income attributable to Westlake Corporation	$ 174	$ 394

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147483443/250-10-50-3

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company is involved in a number of legal and regulatory matters, principally environmental in nature, that are incidental to the normal conduct of its business, including lawsuits, investigations and claims. The outcome of these matters are inherently unpredictable. The Company believes that, in the aggregate, the outcome of all known legal and regulatory matters will not have a material adverse effect on its consolidated financial statements; however, under certain circumstances, if required to recognize costs in a specific period, when combined with other factors, outcomes with respect to such matters may be material to the Company's consolidated statements of operations in such period. The Company's assessment of the potential impact of environmental matters, in particular, is subject to uncertainty due to the complex, ongoing and evolving process of investigation and remediation of such environmental matters, and the potential for technological and regulatory developments. In addition, the impact of evolving claims and programs, such as natural resource damage claims, industrial site reuse initiatives and state remediation programs creates further uncertainty of the ultimate resolution of these matters. The Company anticipates that the resolution of many legal and regulatory matters, and in particular environmental matters, will occur over an extended period of time. Caustic Soda Antitrust. The Company and other caustic soda producers were named as defendants in multiple purported class action civil lawsuits filed since March 2019 in the U.S. District Court for the Western District of New York. The lawsuits allege the defendants conspired to fix, raise, maintain and stabilize the price of caustic soda, restrict domestic (U.S.) supply of caustic soda and allocate caustic soda customers. The other defendants named in the lawsuits are Olin Corporation, K.A. Steel Chemicals (a wholly-owned subsidiary of Olin), Occidental Chemical Corporation d/b/a OxyChem, Shintech Incorporated and Formosa Plastics Corporation, U.S.A. Each of the lawsuits is filed on behalf of the respective named plaintiff or plaintiffs and a putative class comprised of either direct purchasers or indirect purchasers of caustic soda in the U.S. The plaintiffs in the putative class for such direct purchasers seek $861 in single damages from the defendants, in addition to treble damages and attorney's fees. The plaintiffs in the putative class for such indirect purchasers seek approximately $500 in single damages from the defendants, in addition to treble damages (if permitted under applicable state law) and injunctive relief. The defendants' joint motion to dismiss the direct purchaser lawsuits was denied. The defendants' joint motion to dismiss the indirect purchaser lawsuits was granted in part and denied in part. Both groups of cases have proceeded to discovery. On October 16, 2023, the Company entered into a settlement agreement whereby the Company agreed, subject to the terms and conditions of the settlement agreement, to pay $19 to the direct purchaser plaintiffs and in which the Company admits to no violations of law and will be released from liability and dismissed from the direct purchaser lawsuits with prejudice upon receipt of final court approval of the settlement. Preliminary court approval of the settlement, which remains subject to certification of the class, has been requested and is pending. If the court grants such preliminary approval, notice of the settlement will be disseminated to the settlement class, and the settlement class members will, for a limited time period, have an opportunity to opt-out of or object to the settlement. The Company reserved $19 in connection with the litigation in 2023. Beginning in October 2020, similar class action proceedings were also filed in Canada before the Superior Court of Québec as well as before the Federal Court. These proceedings seek the certification or authorization of a class action on behalf of all residents of Canada who purchased caustic soda (including, in one of the cases, those who merely purchased products containing caustic soda) from October 1, 2015 through the present or such date deemed appropriate by the court. On December 10, 2021, the Superior Court of Québec stayed its proceedings until after a final certification decision is released in the Federal Court proceedings. At this time, the Company is not able to estimate the impact, if any, that these lawsuits could have on the Company's consolidated financial statements either in the current period or in future periods. Ethylene Antitrust. The Company and other ethylene consumers were named as defendants in a civil lawsuit filed by Shell Chemical Europe B.V. ("SCE") in March 2023 in the District Court of Amsterdam, the Netherlands, following the European Commission Decision AT.40410 – Ethylene from July 14, 2020. SCE is a producer of ethylene in the European market and the lawsuit alleges the defendants conspired to lower the purchase price for ethylene and ethylene derivatives by manipulating the monthly contract price. SCE initially sought declaratory relief. In October 2023, SCE amended its claim and is now seeking a judgment establishing that the Company and the co-defendants are jointly and severally liable for alleged damages in the amount of approximately €1,026 million with interest compounding daily from January 1, 2020 and continuing until payment in full, as provided by Dutch law, resulting from artificially lowered prices for ethylene and ethylene derivatives during the specified period. SCE is also seeking reimbursement of costs related to the proceeding plus statutory interest. The Company and other ethylene consumers were also named as defendants in a civil lawsuit filed by Stichting Ethylene Claims ("Stichting") in November 2023 in the District Court of Amsterdam, the Netherlands, following the same European Commission decision. Stichting is a foundation under Dutch Law that claims to represent various parties asserting injury by the same alleged conduct of defendants, seeking a declaratory judgment establishing that the Company and other defendants are jointly and severally liable for an unspecified amount of damages. At this time, the Company is not able to estimate the impact, if any, that the SCE lawsuit and/or the Stichting lawsuit could have on the Company's consolidated financial statements either in the current period or in future periods. Triad Hunter. In April 2018, Triad Hunter, LLC ("Triad Hunter") filed suit against the Company and certain of its subsidiaries in the Court of Common Pleas in Monroe County, Ohio seeking injunctive relief and alleging negligence and trespass at the Natrium Plant with respect to Triad Hunter's well drilling activities in Ohio. On October 27, 2022, the jury returned a verdict finding that the Company had committed trespass and was negligent in conducting salt mining operations at the Natrium Plant. Upon receipt of the jury verdict, the Company reserved approximately $70 for the damages awarded to Triad Hunter. The court subsequently denied Triad Hunter's request to enjoin further solution mining from one of the brine fields at the Natrium Plant. On September 12, 2023, final judgment was entered in the amount of $70 with interest accruing at the rate of 5% from the date the judgment was rendered, as provided by law. The Company appealed the verdict and sought a stay of execution pending appeal on October 30, 2023. Petro 2 Flash Fire and EDC Storage Tank Explosion. In September 2021, shortly after the turnaround on Westlake Chemical OpCo LP's Petro 2 ethylene facility commenced, there was a flash fire at the quench tower of the Petro 2 facility. In January 2022, an ethylene dichloride storage tank exploded at one of the Company's Lake Charles, Louisiana complexes. Certain employees and contractors working on the sites at the time of the events were injured during these events and multiple lawsuits were filed against us. Final settlements totaling approximately $382 in the aggregate were reached with all of the plaintiffs to fully resolve the lawsuits, but payment by the Company and the insurance carriers has not yet been completed. Certain of the Company's excess insurers have taken the coverage position that there has been insufficient exhaustion of the retention levels beneath their respective attachment points to obligate them to cover these events. The practical effect of this coverage position is that approximately $150 of the $382 total final settlement amount is not being covered by the insurers and, as such, approximately $150 was included in cost of sales in the fourth quarter of 2023. After discussion with the insurers, the Company has decided not to pursue recovery of the approximately $150 from the insurers. The Company reserved for the full final settlement amount in 2023 and, as of March 31, 2024, has an insurance receivable of $13 and a legal accrual of $151 in the Company's consolidated financial statements. Environmental Contingencies. As of March 31, 2024 and December 31, 2023, the Company had reserves for environmental contingencies totaling approximately $57 and $58, respectively, most of which was classified as noncurrent liabilities. The Company's assessment of the potential impact of these environmental contingencies is subject to considerable uncertainty due to the complex, ongoing and evolving process of investigation and remediation, if necessary, of such environmental contingencies, and the potential for technological and regulatory developments. Calvert City Proceedings. For several years, the Environmental Protection Agency (the "EPA") has been conducting remedial investigation and feasibility studies at the Company's Calvert City, Kentucky facility pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 ("CERCLA"). As the current owner of the Calvert City facility, the Company was named by the EPA as a potentially responsible party ("PRP") along with Goodrich Corporation ("Goodrich") and its successor-in-interest, Avient Corporation (formerly known as PolyOne Corporation, "Avient"). On November 30, 2017, the EPA published a draft Proposed Plan, incorporating by reference an August 2015 draft Remedial Investigation ("RI") report, an October 2017 draft Feasibility Study ("FS") report and a Technical Impracticability Waiver document dated December 19, 2017. On June 18, 2018, the EPA published an amendment to its Proposed Plan. The amended Proposed Plan describes a final remedy for the onshore portion of the site comprised of a containment wall, targeted treatment and supplemental hydraulic containment. The amended Proposed Plan also describes an interim approach to address the contamination under the river that would include recovery of any mobile contaminants by an extraction well along with further study of the extent of the contamination and potential treatment options. The EPA's estimated cost of implementation is $107, with an estimated $1 to $3 in annual operation and maintenance ("O&M") costs. In September 2018, the EPA published the Record of Decision ("ROD") for the site, formally selecting the preferred final and interim remedies outlined in the amended Proposed Plan. In October 2018, the EPA issued Special Notice letters to the PRPs for the remedial design phase of work under the ROD. In April 2019, the PRPs and the EPA entered into an administrative settlement agreement and order on consent for remedial design. In October 2019, the PRPs received special notice letters for the remedial action phase of work at the site. The Company, jointly with the other PRPs, submitted a good faith offer response in December 2019. On September 17, 2020, the EPA and the Department of Justice filed a proposed consent decree for the remedial action with the U.S. District Court for the Western District of Kentucky. On November 16, 2020, the Department of Justice filed a motion to approve and enter the consent decree. On January 28, 2021, the Court granted the unopposed motion to enter the consent decree, which became effective the same day. The Company's allocation of liability for remedial and O&M costs at the Calvert City site, if any, is governed by a series of agreements between the Company, Goodrich and Avient. These agreements and the associated litigation are described below. In connection with the 1990 and 1997 acquisitions of the Goodrich chemical manufacturing complex in Calvert City, Goodrich agreed to indemnify the Company for any liabilities related to preexisting contamination at the complex. 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 complex, which does not include the Company's nearby PVC facility, had been extensively contaminated by Goodrich's operations. In 1993, Goodrich spun off the predecessor of Avient, and that predecessor assumed Goodrich's indemnification obligations relating to preexisting contamination. In 2003, litigation arose among the Company, Goodrich and Avient 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) Avient 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; and (2) either the Company or Avient might, from time to time in the future (but not more than once every five years), institute an arbitration proceeding to adjust that percentage. In May 2017, Avient filed a demand for arbitration. In this proceeding, Avient sought to readjust the percentage allocation of future costs and to recover approximately $11 from the Company in reimbursement of previously paid remediation costs. The Company's cross demand for arbitration seeking unreimbursed remediation costs incurred during the relevant period was dismissed from the proceedings when Avient paid such costs in full at the beginning of the arbitration hearing. On July 10, 2018, Avient sued the Company in the U.S. District Court for the Western District of Kentucky and sought to invalidate the arbitration provisions in the parties' 2007 settlement agreement and enjoin the arbitration it had initiated in 2017. On July 30, 2018, the district court refused to enjoin the arbitration and, on January 15, 2019, the court granted the Company's motion to dismiss Avient's suit. On February 13, 2019, Avient appealed those decisions to the U.S. Court of Appeals for the Sixth Circuit. The court of appeals issued an opinion and final order on September 6, 2019, affirming the district court. The arbitration hearing began in August 2018 and concluded in December 2018. On May 22, 2019, the arbitration panel issued its final award. It determined that Avient was responsible for 100% of the allocable costs at issue in the proceeding and that Avient would remain responsible for 100% of the costs to operate the existing groundwater remedy at the Calvert City site. In August 2019, Avient filed a motion to vacate before the U.S. District Court for the Western District of Kentucky, seeking to invalidate the final award under the Federal Arbitration Act. On February 11, 2020, the U.S. District Court for the Western District of Kentucky denied Avient's motion to vacate and affirmed the arbitration final award. Avient did not file a notice of appeal before the March 10, 2020 deadline to contest the court's decision. Accordingly, the final award was affirmed, and the arbitration proceeding is fully and finally resolved. In March 2022, the Company filed a demand for arbitration seeking reimbursement for certain allocable costs incurred during the applicable period since May 2017, and which Avient has failed to pay or disputed as not subject to indemnity under the 1990 and 1997 agreements. In April 2022, Avient filed a complaint in the federal district court for the Western District of Kentucky disputing the enforceability of the 2007 settlement agreement and seeking to enjoin arbitration. Avient claims that the allocable costs at issue are up to $22, for which Avient claims the Company is totally liable. On September 30, 2023, the court issued an order denying without prejudice the parties' cross motions for summary judgment and set a 30-day deadline for the parties to refile and provide additional briefing on specific aspects of the arguments before the court. The parties each refiled and provided additional briefing by the deadline and the motions are pending before the court. The Company disputes these claims and at this time, the Company believes it is unlikely that any remediation costs allocable to it would result in material expenditures in any individual reporting period. Sulphur Brine Dome. The Company owns and operates salt solution-mining caverns at the Sulphur Brine Dome in Sulphur, Louisiana. The Louisiana Department of Natural Resources issued Compliance Order No. IMD 2022-027 and several supplements to that order, the latest in October 2023, in response to pressure anomaly events in two of the Company's brine caverns. The brine caverns were not active, operating wells but under ongoing, post-operational monitoring requirements. The compliance order and supplements thereto have required the Company to undertake various activities related to response planning, monitoring, investigation and mitigation of potential impacts in the event of future cavern pressure anomalies or failures. Since December 2022 continuous brine injection has maintained cavern pressure while the Company continues to pursue active monitoring, studies, groundwater monitoring, modeling and other activities under the compliance order and supplements. In September 2023, the Office of Conservation issued an emergency declaration as a conservative step and to ensure that the full suite of powers and resources are available to the government in its response and management of the evolving circumstances at the Sulphur Dome. The capital costs and expenditures required to comply with the compliance order and supplements have been and will continue to be incurred. In response to the most recent supplement to the compliance order, the Company reserved approximately $14 in connection with groundwater monitoring wells and monitoring required by the supplement. At this time, the Company is unable to estimate the impact, if any, that other ongoing expenditures or future injunctive relief ordered by the government could have on the Company's consolidated financial statements either in the current period or in future periods. Environmental Remediation: Reasonably Possible Matters. The Company's assessment of the potential impact of environmental contingencies is subject to considerable uncertainty due to the complex, ongoing and evolving process of investigation and remediation, if necessary, of such environmental contingencies, and the potential for technological and regulatory developments. As such, in addition to the amounts currently reserved, the Company may be subject to reasonably possible loss contingencies related to environmental matters in the range of $125 to $200.

Goodwill

3 Months Ended

Mar. 31, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill

The carrying amounts and changes in the carrying amount of goodwill for the three months ended March 31, 2024 were as follows:


	Performance and Essential Materials Segment		Housing and Infrastructure Products Segment		Total
Balances at December 31, 2023	$	897	$	1,144	$	2,041



Effects of changes in foreign exchange rates	(2)		(2)		(4)
Balances at March 31, 2024	$	895	$	1,142	$	2,037

Long-Term Debt (Schedule of Long-term Debt) (Details) € in Millions, $ in Millions	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Total long-term debt, principal amount	$ 4,979		$ 4,997
Unamortized discount and debt issuance costs	89		91
Long-term debt, carrying value	4,890		4,906
Current portion	300		299
Long-term debt, carrying value, net of current portion	$ 4,590		4,607
Senior Notes \| 0.875% Senior Notes Due 2024
Debt Instrument [Line Items]
Stated interest rate (percent)	0.875%	0.875%
Total long-term debt, principal amount	$ 300		300
Current portion	$ 300		299
Senior Notes \| 3.6% Senior Notes Due 2026
Debt Instrument [Line Items]
Stated interest rate (percent)	3.60%	3.60%
Total long-term debt, principal amount	$ 750		750
Senior Notes \| Loan related to tax-exempt waste disposal revenue bonds due 2027
Debt Instrument [Line Items]
Total long-term debt, principal amount	$ 11		11
Senior Notes \| 1.625% Senior Notes Due 2029
Debt Instrument [Line Items]
Stated interest rate (percent)	1.625%	1.625%
Total long-term debt, principal amount	$ 756	€ 700	773
Senior Notes \| 3.375% Senior Notes Due 2030
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%	3.375%
Total long-term debt, principal amount	$ 300		300
Senior Notes \| 3.50% Senior Notes Due 2032
Debt Instrument [Line Items]
Stated interest rate (percent)	3.50%	3.50%
Total long-term debt, principal amount	$ 250		250
Senior Notes \| 2.875% Senior Notes Due 2041
Debt Instrument [Line Items]
Stated interest rate (percent)	2.875%	2.875%
Total long-term debt, principal amount	$ 350		350
Senior Notes \| 5.0% Senior Notes Due 2046
Debt Instrument [Line Items]
Stated interest rate (percent)	5.00%	5.00%
Total long-term debt, principal amount	$ 700		700
Senior Notes \| 4.375% Senior Notes Due 2047
Debt Instrument [Line Items]
Stated interest rate (percent)	4.375%	4.375%
Total long-term debt, principal amount	$ 500		500
Senior Notes \| 3.125% Senior Notes Due 2051
Debt Instrument [Line Items]
Stated interest rate (percent)	3.125%	3.125%
Total long-term debt, principal amount	$ 600		600
Senior Notes \| 3.375% Senior Notes Due 2061
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%	3.375%
Total long-term debt, principal amount	$ 450		450
Senior Notes \| Term Loan Due 2026
Debt Instrument [Line Items]
Total long-term debt, principal amount	$ 12		$ 13

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Summary Of Carrying And Fair Values Of Long-Term Debt

The carrying and fair values of the Company's total long-term debt are summarized below:


	March 31, 2024				December 31, 2023
	Carrying Value		Fair Value		Carrying Value		Fair Value
Long-term debt	$	4,890	$	4,180	$	4,906	$	4,236

Consolidated Statements of Comprehensive Income (Unaudited) Parenthetical - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income (Loss), Tax, Portion Attributable to Noncontrolling Interest	$ 1	$ 1

Accounts Receivable

3 Months Ended

Mar. 31, 2024

Receivables [Abstract]

Accounts Receivable

Accounts receivable consist of the following:


	March 31, 2024		December 31, 2023
Trade customers	$	1,537	$	1,413
Related parties	3		7
Allowance for credit losses	(24)		(27)
	1,516		1,393
Federal and state taxes	59		65
Other	116		143
Accounts receivable, net	$	1,691	$	1,601

Consolidated Statements Of Changes In Stockholders' Equity Statement - USD ($) $ in Millions	Total	Common Stock	Common Stock, Held in Treasury	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Beginning balances at Dec. 31, 2022	$ 10,465	$ 1	$ (467)	$ 601	$ 9,885	$ (89)	$ 534
Beginning balance (in shares) at Dec. 31, 2022		134,651,380
Beginning balance, treasury stock (in shares) at Dec. 31, 2022			7,278,651
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	407				394		13
Other comprehensive loss	22					22	0
Common stock repurchased (in shares)			201,742
Common stock repurchased	(22)		$ (22)
Shares issued—stock- based compensation (in shares)			(469,404)
Shares issued—stock-based compensation	4		$ 24	(20)
Stock-based compensation	9			9
Dividends declared	(47)				(47)
Distributions to noncontrolling interests	(10)						(10)
Ending balances at Mar. 31, 2023	10,828	$ 1	$ (465)	590	10,232	(67)	537
Ending balance (in shares) at Mar. 31, 2023		134,651,380
Ending balance, treasury stock (in shares) at Mar. 31, 2023			7,010,989
Beginning balances at Dec. 31, 2023	10,764	$ 1	$ (435)	630	10,143	(98)	523
Beginning balance (in shares) at Dec. 31, 2023		134,651,380
Beginning balance, treasury stock (in shares) at Dec. 31, 2023			6,439,289
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	185				174		11
Other comprehensive loss	(36)					(34)	(2)
Shares issued—stock- based compensation (in shares)			(357,118)
Shares issued—stock-based compensation	7		$ 21	(14)
Stock-based compensation	8			8
Dividends declared	(65)				(65)
Distributions to noncontrolling interests	(10)						(10)
Ending balances at Mar. 31, 2024	$ 10,853	$ 1	$ (414)	$ 624	$ 10,252	$ (132)	$ 522
Ending balance (in shares) at Mar. 31, 2024		134,651,380
Ending balance, treasury stock (in shares) at Mar. 31, 2024			6,082,171

Basis of Financial Statements (Policies)	3 Months Ended
Basis of Financial Statements (Policies)	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Financial Statements	The accompanying unaudited consolidated interim financial statements were prepared in accordance with the rules and regulations of the Securities and Exchange Commission (the "SEC") for interim periods. Accordingly, certain information and footnotes required for complete financial statements under generally accepted accounting principles in the United States ("U.S. GAAP") have not been included. These interim consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto of Westlake Corporation (the "Company"), included in the annual report on Form 10-K for the fiscal year ended December 31, 2023 (the "2023 Form 10-K"), filed with the SEC on February 22, 2024. These consolidated financial statements have been prepared in conformity with the accounting principles and practices as disclosed in the notes to the consolidated financial statements of the Company for the fiscal year ended December 31, 2023. The Company operates as an integrated global manufacturer and marketer of performance and essential materials and housing and infrastructure products. These products include some of the most widely used materials in the world, which are fundamental to many diverse consumer and industrial markets, including residential construction, flexible and rigid packaging, automotive products, healthcare products, materials used in turbines to generate wind energy, water treatment, coatings 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 throughout North America, Europe and Asia. In the opinion of the Company's management, the accompanying unaudited consolidated interim financial statements reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair statement of the Company's financial position as of March 31, 2024, its results of operations for the three months ended March 31, 2024 and 2023, and the changes in its cash position for the three months ended March 31, 2024 and 2023. Results of operations and changes in cash position for the interim periods presented are not necessarily indicative of the results that will be realized for the fiscal year ending December 31, 2024 or any other interim period. The preparation of consolidated financial statements in conformity with U.S. GAAP 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.
Recent Accounting Pronouncements	Recently Issued Accounting Pronouncements Income Taxes (Topic 740): Improvements to Income Tax Disclosures (ASU No.2023-09) In December 2023, the Financial Accounting Standards Board ("FASB") issued accounting standards update No. 2023-09 to enhance the transparency and decision-usefulness of income tax disclosures and to provide information to better assess how an entity's operations and related tax risks and tax planning and operational opportunities affect its tax rate and prospects for future cash flows. For public business entities, the amendments in this update are effective for annual periods beginning after December 15, 2024. The Company is in the process of evaluating the impact of this standard on the Company's disclosures in the financial statements. Business Combinations—Joint Venture Formations (Subtopic 805-60): Recognition and Initial Measurement (ASU 2023-05) In August 2023, the FASB issued accounting standards update No. 2023-05 to address the accounting for contributions made to a joint venture, upon formation, in a joint venture's financial statements, and to (1) provide decision-useful information to investors and other allocators of capital (collectively, investors) in a joint venture's financial statements and (2) reduce diversity in practice. Under the ASU, upon formation, a joint venture should recognize and initially measure its assets and liabilities at fair value (with exceptions to fair value measurement that are consistent with guidance for business combinations). The amendments in this update become effective for all joint venture formations with a formation date on or after January 1, 2025. Additionally, a joint venture that was formed before January 1, 2025 may elect to apply the amendments retrospectively if it has sufficient information. Early adoption is permitted in any interim or annual period in which financial statements have not yet been issued (or made available for issuance), either prospectively or retrospectively. The Company does not expect that this accounting standard will have a material impact, upon adoption, on the Company's consolidated financial position, results of operations and cash flows. Recently Adopted Accounting Standards Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (ASU 2023-07) In November 2023, the FASB issued accounting standards update No. 2023-07 to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. The update requires public entities to disclose, on an annual and interim basis, significant segment expenses that are regularly provided to the chief operating decision maker (CODM), the title and position of the CODM and an explanation of how the CODM uses the reported measure(s) of segment profit or loss in assessing segment performance and deciding how to allocate resources. The amendments in this update are effective for public entities in fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024, and are to be applied retrospectively to all prior periods presented in the financial statements. Early adoption is permitted. The Company adopted this accounting standard effective January 1, 2024, and the adoption will result in additional segment disclosures in the Company's annual consolidated financial statements for the year ending December 31, 2024 and the interim periods thereafter. Leases (Topic 842): Common Control Arrangements (ASU 2023-01) In March 2023, the FASB issued accounting standards update No. 2023-01 to amend certain provisions of ASC 842 that apply to arrangements between related parties under common control. The update requires all companies to amortize leasehold improvements associated with common control leases over the asset's useful life to the common control group regardless of the lease term. The amendment in this update is effective for all entities in fiscal years beginning after December 15, 2023, including interim periods within those fiscal years. Early application is permitted. The Company adopted this accounting standard effective January 1, 2024, and the adoption did not have a material impact on the Company's consolidated financial position, results of operations and cash flows.

Accounts Receivable (Tables)

3 Months Ended

Mar. 31, 2024

Receivables [Abstract]

Accounts Receivable

Accounts receivable consist of the following:


	March 31, 2024		December 31, 2023
Trade customers	$	1,537	$	1,413
Related parties	3		7
Allowance for credit losses	(24)		(27)
	1,516		1,393
Federal and state taxes	59		65
Other	116		143
Accounts receivable, net	$	1,691	$	1,601

Segment Information (Tables)

3 Months Ended

Mar. 31, 2024

Segment Reporting [Abstract]

Segment Reporting Information


	Three Months Ended March 31,
		2024		2023
Net external sales
Performance and Essential Materials
Performance Materials		$	1,164	$	1,282
Essential Materials		767		1,067
Total Performance and Essential Materials		1,931		2,349
Housing and Infrastructure Products
Housing Products		879		818
Infrastructure Products		165		189
Total Housing and Infrastructure Products		1,044		1,007
		$	2,975	$	3,356

Intersegment sales
Performance and Essential Materials		$	111	$	111
Housing and Infrastructure Products		—		—
		$	111	$	111

Income (loss) from operations
Performance and Essential Materials		$	22	$	403
Housing and Infrastructure Products		210		143
Corporate and other		(9)		(10)
		$	223	$	536

Depreciation and amortization
Performance and Essential Materials		$	220	$	210
Housing and Infrastructure Products		50		55
Corporate and other		3		2
		$	273	$	267

Other income, net
Performance and Essential Materials		$	11	$	2
Housing and Infrastructure Products		4		7
Corporate and other		35		13
		$	50	$	22

Provision for (benefit from) income taxes
Performance and Essential Materials		$	(11)	$	67
Housing and Infrastructure Products		56		37
Corporate and other		3		5
		$	48	$	109


	Three Months Ended March 31,
		2024		2023
Capital expenditures
Performance and Essential Materials		$	230	$	226
Housing and Infrastructure Products		37		38
Corporate and other		5		3
		$	272	$	267

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:


	Three Months Ended March 31,
		2024		2023
Income from operations		$	223	$	536
Interest expense		(40)		(42)
Other income, net		50		22
Income before income taxes		$	233	$	516

Total Assets


	March 31, 2024		December 31, 2023
Total assets
Performance and Essential Materials	$	13,430	$	13,538
Housing and Infrastructure Products	5,078		4,888
Corporate and other	2,452		2,609
	$	20,960	$	21,035

Inventories (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Inventory Disclosure [Abstract]
Finished products	$ 1,055	$ 989
Feedstock, additives, chemicals and other raw materials	372	401
Materials and supplies	234	232
Inventories	$ 1,661	$ 1,622

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 185	$ 407
Pension and other post-retirement benefits liability
Pension and other post-retirement benefits reserves adjustment	1	0
Foreign currency translation adjustments
Foreign currency translation	(33)	20
Income tax (provision) benefit on foreign currency translation	(4)	3
Other, net of income tax	0	(1)
Other comprehensive income (loss), net of income taxes	(36)	22
Comprehensive income	149	429
Comprehensive income attributable to noncontrolling interests, net of tax of $1 and $1 for the three months ended March 31, 2024 and 2023, respectively	9	13
Comprehensive income attributable to Westlake Corporation	$ 140	$ 416

Long-Term Debt (Tables)

3 Months Ended

Mar. 31, 2024

Debt Disclosure [Abstract]

Schedule Of Long-Term Debt

Long-term debt consists of the following:


	March 31, 2024		December 31, 2023


0.875% senior notes due 2024	$	300		$	300
3.60% senior notes due 2026	750			750
Loan related to tax-exempt waste disposal revenue bonds due 2027	11			11
1.625% €700 million senior notes due 2029	756			773
3.375% senior notes due 2030	300			300
3.50% senior notes due 2032	250			250
2.875% senior notes due 2041	350			350
5.00% senior notes due 2046	700			700
4.375% senior notes due 2047	500			500
3.125% senior notes due 2051	600			600
3.375% senior notes due 2061	450			450
Term loans due 2026	12			13
Total long-term debt, principal amount	4,979			4,997
Less:
Unamortized discount and debt issuance costs	89			91
Long-term debt, carrying value	4,890			4,906
Less current portion:
0.875% senior notes due 2024	300			299
Long-term debt, carrying value, net of current portion	$	4,590		$	4,607

- Definition

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.

+ References

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+ Details

Fair Value Measurements

3 Months Ended

Mar. 31, 2024

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). 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 Company has 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 majority of 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.

The carrying and fair values of the Company's total long-term debt are summarized below:


	March 31, 2024				December 31, 2023
	Carrying Value		Fair Value		Carrying Value		Fair Value
Long-term debt	$	4,890	$	4,180	$	4,906	$	4,236

- Definition

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.

+ References + Details

Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Disclosure [Abstract]
Unamortized debt issuance cost	$ 35	$ 36

Financial Instruments	3 Months Ended
Financial Instruments	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Financial Instruments	Financial Instruments Cash Equivalents The Company had $544 and $360 of held-to-maturity securities with original maturities of three months or less, primarily consisting of corporate debt securities, classified as cash equivalents at March 31, 2024 and December 31, 2023, respectively. The Company's investments in held-to-maturity securities were held at amortized cost, which approximates fair value. Restricted Cash and Cash Equivalents The Company had restricted cash and cash equivalents of $16 and $15 at March 31, 2024 and December 31, 2023, respectively. The Company's restricted cash and cash equivalents are primarily related to balances that are restricted for payment of distributions to certain of the Company's current and former employees and are reflected primarily in other assets, net in the consolidated balance sheets.

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Cover Page - shares	3 Months Ended
Cover Page - shares	Mar. 31, 2024	Apr. 25, 2024
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity File Number	001-32260
Entity Registrant Name	Westlake Corporation
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	76-0346924
Entity Address, Address Line One	2801 Post Oak Boulevard
Entity Address, Address Line Two	Suite 600
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77056
City Area Code	713
Local Phone Number	960-9111
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		128,569,968
Amendment Flag	false
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001262823
Current Fiscal Year End Date	--12-31
Common Stock
Document Information [Line Items]
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	WLK
Security Exchange Name	NYSE
1.625% Senior Notes Due 2029
Document Information [Line Items]
Title of 12(b) Security	1.625% Senior Notes due 2029
Trading Symbol	WLK29
Security Exchange Name	NYSE

Earnings and Dividends per Share (Reconciliation of Denominator for Basic and Diluted Earnings Per Share) (Details) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings and Dividends Per Share [Abstract]
Weighted average common shares—basic	128,359,983	127,548,287
Weighted Average Number Diluted Shares Outstanding Adjustment	660,387	911,081
Weighted average common shares-diluted	129,020,370	128,459,368
Earnings per share attributable to Westlake Corporation: Basic (in dollars per share)	$ 1.35	$ 3.07
Earnings per share attributable to Westlake Corporation: Diluted (in dollars per share)	$ 1.34	$ 3.05

- Definition

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

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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

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+ Details

Earnings and Dividends per Share (Additional Information) (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings and Dividends Per Share [Abstract]
Number of options excluded from computation of diluted earnings per share	260,722	307,411

Supplemental Information (Additional Information) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Accrued Liabilities and Other Liabilities [Abstract]
Other assets, net	$ 694		$ 651
Deferred turnaround costs, net	420		391
Accrued and other liabilities	1,464		1,614
Accrued rebates	158		217
Estimated Litigation Liability, Current	267		297
Accrued income taxes	136		121
Noncash Investing and Financing Items [Abstract]
Capital expenditures incurred but not yet paid	112	$ 111
Asset Retirement Obligation, Revision of Estimate	16
Other Income and Expenses [Abstract]
Other income, net	50	22
Interest income, other	40	18
Supplemental Cash Flow Information [Abstract]
Interest, net of interest capitalized	52	54
Income taxes	46	23
Right-of-use assets obtained in exchange for operating lease obligations	44	$ 56
Related Party
Related Party Transaction [Line Items]
Other liabilities, current	$ 37		$ 41

Earnings and Dividends per Share (Schedule of Net Income Attributable to Common Stockholders) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings and Dividends Per Share [Abstract]
Net income attributable to Westlake Corporation	$ 174	$ 394
Net income attributable to participating securities	(1)	(2)
Net income attributable to common shareholders	$ 173	$ 392

- Definition

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

+ References

+ Details

Accumulated Other Comprehensive Income (Loss) (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ (98)	$ (89)
Ending balance	(132)	(67)
Pension and Other Post-Retirement Benefits Liability, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	4	52
Net other comprehensive income (loss) attributable to Westlake Corporation	1	0
Ending balance	5	52
Cumulative Foreign Currency Exchange, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(102)	(141)
Net other comprehensive income (loss) attributable to Westlake Corporation	(35)	23
Ending balance	(137)	(118)
Other, Net of Tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	0
Net other comprehensive income (loss) attributable to Westlake Corporation	0	(1)
Ending balance	0	(1)
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Net other comprehensive income (loss) attributable to Westlake Corporation	$ (34)	$ 22

- Definition

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

+ References + Details

Supplemental Information (Tables)

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Changes in Investment

The Company accounts for its investment in LACC under the equity method of accounting and the change for the three months ended March 31, 2024 was as follows:


	Investment in LACC





Balance at December 31, 2023	$	1,047


Depreciation and amortization	(12)

Balance at March 31, 2024	$	1,035

Schedule of Cash Flow Information

Supplemental Cash Flow Information


	Three Months Ended March 31,
	2024		2023
Cash paid for:
Interest, net of interest capitalized	$	52	$	54
Income taxes	46		23
Operating lease information:
Right-of-use assets obtained in exchange for operating lease obligations	$	44	$	56

Earnings and Dividends per Share (Dividends per Share) (Details) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings and Dividends Per Share [Abstract]
Dividends per common share (in usd per share)	$ 0.5000	$ 0.3570

Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Current assets
Cash and cash equivalents	$ 3,108	$ 3,304
Accounts receivable, net	1,691	1,601
Inventories	1,661	1,622
Prepaid expenses and other current assets	66	82
Total current assets	6,526	6,609
Property, plant and equipment, net	8,523	8,519
Operating lease right-of-use assets	706	697
Goodwill	2,037	2,041
Customer relationships, net	889	910
Other intangible assets, net	481	493
Equity method investments	1,104	1,115
Other assets, net	694	651
Total assets	20,960	21,035
Current liabilities
Accounts payable	891	877
Accrued and other liabilities	1,464	1,614
Current portion of long-term debt, net	300	299
Total current liabilities	2,655	2,790
Long-term debt, net	4,590	4,607
Deferred income taxes	1,544	1,560
Pension and other post-retirement benefits	353	363
Operating lease liabilities	622	611
Other liabilities	343	340
Total liabilities	10,107	10,271
Commitments and contingencies (Note 13)
Stockholders' equity
Preferred stock, $0.01 par value, 50,000,000 shares authorized; no shares issued and outstanding	0	0
Common stock, $0.01 par value, 300,000,000 shares authorized; 134,651,380 and 134,651,380 shares issued at March 31, 2024 and December 31, 2023, respectively	1	1
Common stock, held in treasury, at cost; 6,082,171 and 6,439,289 shares at March 31, 2024 and December 31, 2023, respectively	(414)	(435)
Additional paid-in capital	624	630
Retained earnings	10,252	10,143
Accumulated other comprehensive loss	(132)	(98)
Total Westlake Corporation stockholders' equity	10,331	10,241
Noncontrolling interests	522	523
Total equity	10,853	10,764
Total liabilities and equity	$ 20,960	$ 21,035