Statement of Consolidated Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
NET INCOME (LOSS) INCLUDING NONCONTROLLING INTEREST	$ (5,060)us-gaap_ProfitLoss	$ 2,288us-gaap_ProfitLoss	$ 2,001us-gaap_ProfitLoss
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and postretirement benefit plan, net of tax		9	(2)
Commodity cash flow hedge activity, net of tax:
Reclassification of (gain) loss on settled derivative instruments		11	(199)
Change in fair value of derivative instruments	(1)	(5)	79
Derivative hedge ineffectiveness reclassified into earnings		1
Commodity cash flow hedge activity, net of tax	(1)	16	(122)
COMPREHENSIVE INCOME (LOSS) INCLUDING NONCONTROLLING INTEREST	(5,061)	2,304	1,879
Preferred stock dividends		44us-gaap_DividendsPreferredStockStock	76us-gaap_DividendsPreferredStockStock
Comprehensive income attributable to noncontrolling interest	343	56
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO COMMON STOCK	$ (5,404)us-gaap_ComprehensiveIncomeNetOfTax	$ 2,204us-gaap_ComprehensiveIncomeNetOfTax	$ 1,803us-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 of paid and unpaid preferred stock dividends declared with the form of settlement in stock.

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-Publisher SEC

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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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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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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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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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