Unaudited Interim Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2026	Mar. 31, 2025
Statement of Comprehensive Income [Abstract]
Net earnings (loss)		$ 48	$ (20)
Other comprehensive income (loss), net of tax
Foreign currency translation gain (loss)	[1]	(27)	(5)
Gain (loss) on derivative hedges		(6)	35
Pension and postretirement benefits		0	1
Total other comprehensive income (loss), net of tax		(33)	31
Total comprehensive income (loss), net of tax		15	11
Comprehensive (income) loss attributable to noncontrolling interests		(6)	(4)
Comprehensive income (loss) attributable to Celanese Corporation		$ 9	$ 7

[1] Includes gross foreign currency translation adjustments related to noncontrolling interests of $2 million and $0 million for the three months ended March 31, 2026 and 2025, respectively.