v3.19.2

Income Taxes (Income Tax Expense (Benefit)) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Income Tax Contingency [Line Items] |  |  |  |
Income tax expense (benefit) | $ 9 | $ (158) | $ 19 | $ (50)
Effective Income Tax Rate, Continuing Operations | 3.00% | (81.00%) | 4.00% | 17.00%
Income Tax Uncertainties [Abstract] |  |  |  |
Unrecognized Tax Benefits | $ 29 |  | $ 29 |
Unrecognized Tax Benefits that Would Impact Effective Tax Rate | 17 |  | 17 |
Unrecognized Tax Benefit Related to Deferred Tax Asset | 12 |  | 12 |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued | 3 |  | 3 |
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 | $ 8 |  | $ 8 |

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