Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income (loss)	$ (641)us-gaap_ProfitLoss	$ 616us-gaap_ProfitLoss
Other comprehensive income (loss), net of income taxes:
Defined benefit and other postretirement plan adjustments	3	3
Other	(6)	1
Other comprehensive income (loss), net of income taxes	(3)	4
Comprehensive income (loss)	(644)	620
Comprehensive (income) loss attributable to noncontrolling interest	(2)	6
Comprehensive income (loss) attributable to company shareholders	$ (646)us-gaap_ComprehensiveIncomeNetOfTax	$ 626us-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 of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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