Income Taxes (Schedule of Provision for Income Taxes for Income from Continuing Operations) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current:
Federal	$ (29)us-gaap_CurrentFederalTaxExpenseBenefit	$ 27us-gaap_CurrentFederalTaxExpenseBenefit	$ 99us-gaap_CurrentFederalTaxExpenseBenefit
State	3	6	10
Total, Current	(26)us-gaap_CurrentIncomeTaxExpenseBenefit	33us-gaap_CurrentIncomeTaxExpenseBenefit	109us-gaap_CurrentIncomeTaxExpenseBenefit
Deferred:
Federal	106	60	58
State	2	11	(3)
Total, Deferred	108us-gaap_DeferredIncomeTaxExpenseBenefit	71us-gaap_DeferredIncomeTaxExpenseBenefit	55us-gaap_DeferredIncomeTaxExpenseBenefit
Total provision for income taxes for income from continuing operations	$ 82us-gaap_IncomeTaxExpenseBenefit	$ 104us-gaap_IncomeTaxExpenseBenefit	$ 164us-gaap_IncomeTaxExpenseBenefit

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

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

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

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

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

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