Accumulated Other Comprehensive Income (Loss) (Tables)

3 Months Ended

Mar. 31, 2025

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, 2025 and 2024 were as follows:

	Pension and Other Post-Retirement Benefits Liability, Net of Tax		Cumulative Foreign Currency Exchange, Net of Tax		Total
Balances at December 31, 2024	$	54	$	(198)	$	(144)
Net other comprehensive income attributable to Westlake Corporation	—		14		14
Balances at March 31, 2025	$	54	$	(184)	$	(130)
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)