Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 412	$ 620	$ 2,049	$ 1,409
Pension and other post-retirement benefits liability
Pension and other post-retirement benefits reserves adjustment	0	1	1	1
Income tax provision on pension and other post-retirement benefits liability	0	(1)	0	(1)
Foreign currency translation adjustments
Foreign currency translation	(106)	(13)	(175)	2
Income tax provision on foreign currency translation	(13)	(6)	(29)	(13)
Other comprehensive loss, net of income taxes	(119)	(19)	(203)	(11)
Comprehensive income	293	601	1,846	1,398
Comprehensive income attributable to noncontrolling interests, net of tax of $1 and $1 for the three months ended September 30, 2022 and 2021; and net of tax of $3 and $2 for the nine months ended September 30, 2022 and 2021, respectively	7	13	26	38
Comprehensive income attributable to Westlake Corporation	$ 286	$ 588	$ 1,820	$ 1,360