Earnings (Loss) Per Share (Schedule of Earnings (Loss) Per Share) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Amounts attributable to Celanese Corporation
Earnings (loss) from continuing operations	$ 265	$ 161	$ 742	$ 604
Earnings (loss) from discontinued operations	(3)	0	(2)	(2)
Net earnings (loss)	$ 262	$ 161	$ 740	$ 602
Weighted average shares - basic	144,005,098	149,800,029	145,959,821	152,153,057
Incremental shares attributable to equity awards	596,367	1,204,052	625,739	1,267,392
Weighted average shares - diluted	144,601,465	151,004,081	146,585,560	153,420,449