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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2017
Income Tax Disclosure [Abstract] |  |  |
Effective income tax rate | 15.90% |  | 0.10%
Income taxes | $ 114 |  | $ 0
Income from continuing operations before income taxes | $ 718 |  | $ 265
Provisional income tax expense |  | $ 345 |

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