Earnings (Loss) Per Share (Schedule of Earnings (Loss) Per Share) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Amounts attributable to Celanese Corporation
Earnings (loss) from continuing operations	$ 256	$ 236
Earnings (loss) from discontinued operations	1	0
Net earnings (loss)	$ 257	$ 236
Weighted average shares - basic	147,413,234	153,216,510
Incremental shares attributable to equity awards	717,880	685,052
Weighted average shares - diluted	148,131,114	153,901,562

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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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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