Consolidated Statements of Comprehensive (Loss) Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net (loss) income	$ (2,406)us-gaap_ProfitLoss	$ 626us-gaap_ProfitLoss
Defined benefit plans:
Amortization of unrecognized amounts included in net periodic benefit costs	8	3
Foreign exchange gains	4	0
Other comprehensive income	12	3
Total comprehensive (loss) income	(2,394)	629
Total comprehensive income attributable to noncontrolling interests	(58)	(106)
Preferred dividends attributable to redeemable noncontrolling interest	(10)	(10)
Total comprehensive (loss) income attributable to common stockholders	$ (2,462)us-gaap_ComprehensiveIncomeNetOfTax	$ 513us-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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