Consolidated Statements of Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net earnings (loss)	$ 234us-gaap_ProfitLoss	$ 195us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax
Unrealized gain (loss) on marketable securities	0	0
Foreign currency translation	(156)	5
Gain (loss) on cash flow hedges	2	(3)
Pension and postretirement benefits	(3)	(12)
Total other comprehensive income (loss), net of tax	(157)	(10)
Total comprehensive income (loss), net of tax	77	185
Comprehensive (income) loss attributable to noncontrolling interests	2	1
Comprehensive income (loss) attributable to Celanese Corporation	$ 79us-gaap_ComprehensiveIncomeNetOfTax	$ 186us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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