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