Earnings (Loss) Per Share (Schedule of Earnings (Loss) Per Share) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Amounts attributable to Celanese Corporation
Earnings (loss) from continuing operations	$ 221	$ 207	$ 477	$ 443
Earnings (loss) from discontinued operations	0	(2)	1	(2)
Net earnings (loss)	$ 221	$ 205	$ 478	$ 441
Weighted average shares - basic	146,482,612	153,480,175	146,947,923	153,349,071
Incremental shares attributable to equity awards	583,076	510,758	644,608	596,395
Weighted average shares - diluted	147,065,688	153,990,933	147,592,531	153,945,466