Unaudited Interim Consolidated Statement Equity - USD ($) $ in Millions	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss), Net	Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Celanese Corporation stockholders' equity		$ 0	$ (5,492)	$ 333	$ 9,677	$ (329)
Balance as of the beginning of the period (in shares) at Dec. 31, 2021		108,023,735	61,736,289
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation, net of tax				(7)
Purchases of treasury stock (in shares)	0		0
Purchases of treasury stock, including related fees			$ 0
Stock awards (in shares)		283,606
Stock awards		$ 0
Net earnings (loss) attributable to Celanese Corporation	$ 502				502
Common stock dividends					(73)
Other comprehensive income (loss), net of tax	(4)					(4)
Balance as of the beginning of the period, noncontrolling interest at Dec. 31, 2021							$ 348
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss) attributable to noncontrolling interests	2						2
Dividends to noncontrolling interests							0
Distributions to noncontrolling interests							(4)
Balance as of the end of the period, noncontrolling interest at Mar. 31, 2022							346
Balance as of the end of the period (in shares) at Mar. 31, 2022		108,307,341	61,736,289
Balance as of the end of the period at Mar. 31, 2022	4,953
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Celanese Corporation stockholders' equity	4,607	$ 0	$ (5,492)	326	10,106	(333)
Celanese Corporation stockholders' equity	5,637	$ 0	$ (5,491)	372	11,274	(518)
Balance as of the beginning of the period (in shares) at Dec. 31, 2022		108,473,932	61,661,493
Balance as of the beginning of the period at Dec. 31, 2022	$ 6,105
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation, net of tax				(7)
Purchases of treasury stock (in shares)	0		0
Purchases of treasury stock, including related fees			$ 0
Stock awards (in shares)		312,806
Stock awards		$ 0
Net earnings (loss) attributable to Celanese Corporation	$ 91				91
Common stock dividends					(76)
Other comprehensive income (loss), net of tax	16					16
Balance as of the beginning of the period, noncontrolling interest at Dec. 31, 2022	468						468
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss) attributable to noncontrolling interests	2						2
Dividends to noncontrolling interests							(1)
Distributions to noncontrolling interests							0
Balance as of the end of the period, noncontrolling interest at Mar. 31, 2023	469						$ 469
Balance as of the end of the period (in shares) at Mar. 31, 2023		108,786,738	61,661,493
Balance as of the end of the period at Mar. 31, 2023	6,130
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Celanese Corporation stockholders' equity	$ 5,661	$ 0	$ (5,491)	$ 365	$ 11,289	$ (502)