Unaudited Interim Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ (1,353)	$ 117	$ (1,173)	$ 388
Other comprehensive income (loss), net of tax
Foreign currency translation gain (loss)	26	53	(48)	(9)
Gain (loss) on derivative hedges	29	16	49	30
Pension and postretirement benefits	0	0	0	(1)
Total other comprehensive income (loss), net of tax	55	69	1	20
Total comprehensive income (loss), net of tax	(1,298)	186	(1,172)	408
Comprehensive (income) loss attributable to noncontrolling interests	(5)	(8)	(13)	(8)
Comprehensive income (loss) attributable to Celanese Corporation	$ (1,303)	$ 178	$ (1,185)	$ 400