Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ (1,151)	$ (1,534)	$ 1,947
Other comprehensive income (loss), net of tax
Foreign currency translation gain (loss)	0	(101)	(213)
Gain (loss) on derivative hedges	63	0	(6)
Pension and postretirement benefits	14	(5)	(7)
Total other comprehensive income (loss), net of tax	77	(106)	(226)
Total comprehensive income (loss), net of tax	(1,074)	(1,640)	1,721
Comprehensive (income) loss attributable to noncontrolling interests	(19)	(6)	(4)
Comprehensive income (loss) attributable to Celanese Corporation	$ (1,093)	$ (1,646)	$ 1,717