Consolidated Statements of Equity - USD ($) $ in Millions	Total		Series A Common Stock [Member]	Treasury Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss), Net [Member]	Noncontrolling Interests [Member]
Balance as of the beginning of the period, shares at Dec. 31, 2012			159,642,401	23,986,836
Balance as of the beginning of the period at Dec. 31, 2012								$ 0
Balance as of the beginning of the year at Dec. 31, 2012			$ 0	$ (905)	$ 731	$ 1,993	$ (89)
Stock option exercises, net of tax	$ 6		$ 0		11
Stock option exercises, shares			283,682
Purchases of treasury stock, shares			(3,192,201)
Purchases of treasury stock			$ 0
Stock awards, shares			205,946
Stock awards			$ 0
Purchases of treasury stock, shares	3,186,180	[1]		3,192,201
Purchases of treasury stock, including related fees	$ (164)			$ (164)
Retirement of treasury stock, shares				(18,250,900)
Retirement of treasury stock				$ (708)	(708)
Stock-based compensation, net of tax					19
Net earnings (loss) attributable to Celanese Corporation	1,101					1,101
Series A common stock dividends						(83)
Other comprehensive income (loss), net of tax	85						85
Balance as of the end of the year at Dec. 31, 2013	2,699		$ 0	$ (361)	53	3,011	(4)
Balance as of the end of the period, shares at Dec. 31, 2013			156,939,828	8,928,137
Net earnings (loss) attributable to noncontrolling interests	0							0
Contributions from noncontrolling interests								0
Balance as of the end of the period at Dec. 31, 2013								0
Total equity at Dec. 31, 2013	2,699
Stock option exercises, net of tax	$ 7		$ 0		7
Stock option exercises, shares			202,121
Purchases of treasury stock, shares			(4,338,488)
Purchases of treasury stock			$ 0
Stock awards, shares			99,249
Stock awards			$ 0
Purchases of treasury stock, shares	4,338,488	[1]		4,338,488
Purchases of treasury stock, including related fees	$ (250)			$ (250)
Retirement of treasury stock, shares				0
Retirement of treasury stock				$ 0	0
Stock-based compensation, net of tax					43
Net earnings (loss) attributable to Celanese Corporation	624					624
Series A common stock dividends						(144)
Other comprehensive income (loss), net of tax	(161)						(161)
Balance as of the end of the year at Dec. 31, 2014	2,818		$ 0	$ (611)	103	3,491	(165)
Balance as of the end of the period, shares at Dec. 31, 2014			152,902,710	13,266,625
Net earnings (loss) attributable to noncontrolling interests	(4)							(4)
Contributions from noncontrolling interests								264
Balance as of the end of the period at Dec. 31, 2014	260							260
Total equity at Dec. 31, 2014	3,078
Stock option exercises, net of tax	$ 4		$ 0		5
Stock option exercises, shares	94,000		94,147
Purchases of treasury stock, shares			(6,649,865)
Purchases of treasury stock			$ 0
Stock awards, shares			435,305
Stock awards			$ 0
Purchases of treasury stock, shares	6,640,601	[1]		6,649,865
Purchases of treasury stock, including related fees	$ (420)			$ (420)
Retirement of treasury stock, shares				0
Retirement of treasury stock				$ 0	0
Stock-based compensation, net of tax					28
Net earnings (loss) attributable to Celanese Corporation	304					304
Series A common stock dividends						(174)
Other comprehensive income (loss), net of tax	(183)						(183)
Balance as of the end of the year at Dec. 31, 2015	2,378		$ 0	$ (1,031)	$ 136	$ 3,621	$ (348)
Balance as of the end of the period, shares at Dec. 31, 2015			146,782,297	19,916,490
Net earnings (loss) attributable to noncontrolling interests	(19)							(19)
Contributions from noncontrolling interests								210
Balance as of the end of the period at Dec. 31, 2015	451							$ 451
Total equity at Dec. 31, 2015	$ 2,829

[1] The years ended December 31, 2015 and 2013 exclude 9,264 and 6,021 shares, respectively, withheld from an executive officer to cover statutory minimum withholding requirements for personal income taxes related to the vesting of restricted stock. Restricted stock awards are considered outstanding at the time of issuance. Accordingly, the shares withheld are treated as treasury shares.