v3.19.1

Income Taxes (Income Tax Expense (Benefit)) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
Income Tax Contingency [Line Items] |  |
Income tax (expense) benefit | $ (10) | $ (108)
Effective Income Tax Rate, Continuing Operations | 5.00% | (22.00%)
Income Tax Uncertainties [Abstract] |  |
Unrecognized Tax Benefits | $ 28 |
Unrecognized Tax Benefits that Would Impact Effective Tax Rate | 16 |
Unrecognized Tax Benefit Related to Deferred Tax Asset | 12 |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 2 |
Minimum [Member] |  |
Income Tax Contingency [Line Items] |  |
Decrease in Unrecognized Tax Benefits is Reasonably Possible | 0 |
Maximum [Member] |  |
Income Tax Contingency [Line Items] |  |
Decrease in Unrecognized Tax Benefits is Reasonably Possible | $ 8 |

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