Unaudited Interim Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2026		Sep. 30, 2025		Sep. 30, 2026		Sep. 30, 2025
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ 78		$ (1,353)		$ 255		$ (1,173)
Other comprehensive income (loss), net of tax
Foreign currency translation gain (loss)	(26)	[1]	26	[1]	(68)	[2]	(48)	[2]
Gain (loss) on derivative hedges	(2)		29		(21)		49
Pension and postretirement benefits	0		0		(1)		0
Total other comprehensive income (loss), net of tax	(28)		55		(90)		1
Total comprehensive income (loss), net of tax	50		(1,298)		165		(1,172)
Comprehensive (income) loss attributable to noncontrolling interests	(6)		(5)		(18)		(13)
Comprehensive income (loss) attributable to Celanese Corporation	$ 44		$ (1,303)		$ 147		$ (1,185)

[1] Includes gross foreign currency translation adjustments related to noncontrolling interests of $2 million and $1 million for the three months ended September 30, 2026 and 2025, respectively.

[2] Includes gross foreign currency translation adjustments related to noncontrolling interests of $6 million and $2 million for the nine months ended September 30, 2026 and 2025, respectively.