Earnings (Loss) Per Share (Schedule of Earnings (Loss) Per Share) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012		Jun. 30, 2013	Jun. 30, 2012
Amounts attributable to Celanese Corporation
Earnings (loss) from continuing operations	$ 133	$ 221	[1]	$ 274	$ 414	[1]
Earnings (loss) from discontinued operations	0	0		1	0
Net earnings (loss) available to common stockholders	$ 133	$ 221	[1]	$ 275	$ 414	[1]
Weighted average shares - basic	159,676,462	158,163,378		159,679,408	157,370,137
Dilutive stock options	213,834	1,014,359		216,890	1,434,687
Dilutive restricted stock units	251,860	600,518		242,661	641,919
Weighted average shares - diluted	160,142,156	159,778,255		160,138,959	159,446,743

[1] As Adjusted (Note 1)