Earnings (Loss) Per Share (Schedule of Earnings (Loss) Per Share) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Amounts attributable to Celanese Corporation
Earnings (loss) from continuing operations	$ 183	$ 256
Earnings (loss) from discontinued operations	0	1
Net earnings (loss)	$ 183	$ 257
Weighted average shares - basic	140,643,860	147,413,234
Incremental shares attributable to equity awards	353,543	717,880
Weighted average shares - diluted	140,997,403	148,131,114

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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