Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 2,070	$ 373	$ 462
Pension and other post-retirement benefits
Pension and other post-retirement benefits reserves adjustment	60	(37)	(32)
Income tax benefit (provision) on pension and other post-retirement benefits	(16)	10	8
Foreign currency translation adjustments
Foreign currency translation	2	23	17
Income tax benefit (provision) on foreign currency translation	(17)	18	(4)
Other comprehensive income (loss), net of income taxes	29	14	(11)
Comprehensive income	2,099	387	451
Comprehensive income attributable to noncontrolling interests, net of tax of $2, $1 and $2 for 2021, 2020 and 2019, respectively	56	47	42
Comprehensive income attributable to Westlake Corporation	$ 2,043	$ 340	$ 409