Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Contingency [Line Items]
Income (Loss) from Continuing Operations Before Income Taxes	$ (300)	$ 168	$ (169)	$ 54
Income Taxes	$ 39	$ 74	$ 49	$ 16
Effective Tax Rate	(13.00%)	44.00%	(29.00%)	30.00%
Annualized effective tax rate			30.76%	36.93%
State deferred taxes			$ 17
IRS
Income Tax Contingency [Line Items]
Tax benefit recorded for previously unrecognized tax benefits			$ 12

Effective Income Tax Rate Reconciliation, Interim Period, Annualized Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Glossary Income Tax Expense (or Benefit)

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in state and local income tax contingency.

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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