Provision (Benefit) for Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Income Tax Contingency [Line Items]
Provision For Adjustment To Prior Year Taxable Foreign Income	$ 14
Current :
Federal	0us-gaap_CurrentFederalTaxExpenseBenefit	137us-gaap_CurrentFederalTaxExpenseBenefit
State	0	5
Foreign	2us-gaap_CurrentForeignTaxExpenseBenefit	2us-gaap_CurrentForeignTaxExpenseBenefit
Total	2us-gaap_CurrentIncomeTaxExpenseBenefit	144us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred:
Federal	25	(96)
State	3	(1)
Foreign	0	4
Total	28us-gaap_DeferredIncomeTaxExpenseBenefit	(93)us-gaap_DeferredIncomeTaxExpenseBenefit
Total provision (benefit)	$ 30us-gaap_IncomeTaxExpenseBenefit	$ 51us-gaap_IncomeTaxExpenseBenefit

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of deferred foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.

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