v3.8.0.1

Income Taxes (Income Tax Expense (Benefit)) (Details) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Dec. 31, 2016 USD ($)
Income Tax Contingency [Line Items] |  |  |  |  |
Income tax (expense) benefit | $ 2 | $ 4 | $ 0 | $ (17) |
Effective Income Tax Rate, Continuing Operations | (1.00%) | (1.00%) | 0.00% | 20.00% |
Income Tax Uncertainties [Abstract] |  |  |  |  |
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions |  |  | $ 17 |  |
Number of States for NOL Carryforwards |  |  |  |  | 21
Unrecognized Tax Benefits | $ 48 |  | 48 |  |
Unrecognized Tax Benefits that Would Impact Effective Tax Rate | 10 |  | 10 |  |
Unrecognized Tax Benefit Related to Deferred Tax Asset | 38 |  | 38 |  |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 4 |  | 4 |  |
Minimum [Member] |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Decrease in Unrecognized Tax Benefits is Reasonably Possible | 0 |  | 0 |  |
Maximum [Member] |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Decrease in Unrecognized Tax Benefits is Reasonably Possible | $ 7 |  | $ 7 |  |
Expiration date 2024 through 2033 [Member] |  |  |  |  |
Income Tax Uncertainties [Abstract] |  |  |  |  |
Deferred Tax Assets, Operating Loss Carryforwards, Domestic |  |  |  |  | $ 6,700
Expiration date 2017 through 2036 [Member] |  |  |  |  |
Income Tax Uncertainties [Abstract] |  |  |  |  |
Deferred Tax Assets, Operating Loss Carryforwards, State and Local |  |  |  |  | 3,700
Expiration date 2025 through 2033 [Member] |  |  |  |  |
Income Tax Uncertainties [Abstract] |  |  |  |  |
Deferred Tax Assets, Operating Loss Carryforwards, Foreign |  |  |  |  | 647
Foreign Tax Authority [Member] |  |  |  |  |
Income Tax Uncertainties [Abstract] |  |  |  |  |
Deferred Tax Assets, Net of Valuation Allowance |  |  |  |  | 161
Deferred Tax Assets, Valuation Allowance |  |  |  |  | $ 101

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