Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Noncontrolling Interest in OpCo	Westlake General Partner	Common units Publicly and Privately Held Limited Partner	Common units Westlake Limited Partner
Equity, beginning balance at Dec. 31, 2021	$ 972,698	$ 678,720	$ (242,572)	$ 481,796	$ 54,754
Stockholders' Equity [Roll Forward]
Net income	334,829	270,656	0	38,439	25,734
Units issued for vested phantom units	190			190
Distribution to unitholders	(66,411)			(39,782)	(26,629)
Distribution to noncontrolling interest retained in OpCo by Westlake	(337,598)	(337,598)
Equity, ending balance at Dec. 31, 2022	903,708	611,778	(242,572)	480,643	53,859
Stockholders' Equity [Roll Forward]
Net income	334,626	280,343	0	32,519	21,764
Units issued for vested phantom units	141			141
Distribution to unitholders	(66,420)			(39,790)	(26,630)
Distribution to noncontrolling interest retained in OpCo by Westlake	(315,805)	(315,805)
Equity, ending balance at Dec. 31, 2023	856,250	576,316	(242,572)	473,513	48,993
Stockholders' Equity [Roll Forward]
Net income	369,159	306,767	0	37,384	25,008
Units issued for vested phantom units	238			238
Distribution to unitholders	(66,435)			(39,807)	(26,628)
Distribution to noncontrolling interest retained in OpCo by Westlake	(329,898)	(329,898)
Equity, ending balance at Dec. 31, 2024	$ 829,314	$ 553,185	$ (242,572)	$ 471,328	$ 47,373