Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 873	$ 536	$ 1,637	$ 789
Pension and other post-retirement benefits reserves adjustment	1	0	1	0
Foreign currency translation adjustments
Foreign currency translation	(61)	12	(69)	15
Income tax benefit (provision) on foreign currency translation	(13)	3	(16)	(7)
Other comprehensive income (loss), net of income taxes	(73)	15	(84)	8
Comprehensive income	800	551	1,553	797
Comprehensive income attributable to noncontrolling interests, net of tax of $1 and $1 for the three months ended June 30, 2022 and 2021; and net of tax of $2 and $1 for the six months ended June 30, 2022 and 2021, respectively	13	15	19	25
Comprehensive income attributable to Westlake Corporation	$ 787	$ 536	$ 1,534	$ 772