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 attributable to Union Carbide Corporation	$ 375	$ 427	$ 627
Other comprehensive income (loss), net of tax
Cumulative translation adjustments	2	1	1
Pension and other postretirement benefit plans	217	(106)	(105)
Net other comprehensive income	219	(105)	(104)
Comprehensive income attributable to Union Carbide Corporation	$ 594	$ 322	$ 523