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Income Taxes - Income from continuing operations before income tax (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income before income taxes: |  |  |
Income before income taxes: | $ 1,871 | $ 1,246 | $ 685
Current: |  |  |
Total current tax expense | 333 | 371 | 268
Deferred tax expense (benefit): |  |  |
Total deferred tax benefit | (36) | (225) | (18)
Total income tax expense | 297 | 146 | 250
U.K. |  |  |
Income before income taxes: |  |  |
Income before income taxes: | 228 | (240) | (420)
Current: |  |  |
Total current tax expense | 20 | 21 | 1
Deferred tax expense (benefit): |  |  |
Total deferred tax benefit | 35 | 19 | (5)
U.S. federal |  |  |
Income before income taxes: |  |  |
Income before income taxes: | (219) | (601) | (765)
Current: |  |  |
Total current tax expense | 22 | 101 | 48
Deferred tax expense (benefit): |  |  |
Total deferred tax benefit | (20) | (165) | 12
U.S. state and local |  |  |
Current: |  |  |
Total current tax expense | 41 | 35 | 18
Deferred tax expense (benefit): |  |  |
Total deferred tax benefit | (27) | (56) | (35)
Other |  |  |
Income before income taxes: |  |  |
Income before income taxes: | 1,862 | 2,087 | 1,870
Current: |  |  |
Total current tax expense | 250 | 214 | 201
Deferred tax expense (benefit): |  |  |
Total deferred tax benefit | $ (24) | $ (23) | $ 10

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