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Income Taxes (Effective Rate Reconciliation) (Details) - USD ($) $ in Millions |  |  | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 22, 2017 | Dec. 21, 2017 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Income Tax Contingency [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
U.S. statutory rate (as a percent) | 21.00% | 35.00% |  |  |  |  |  |  |  |  | 21.00% | 35.00% |
Tax (expense) benefit at the U.S. statutory rate |  |  |  |  |  |  |  |  |  |  | $ (85.1) | $ 37.4 | $ (2.7)
Differences in taxes resulting from: |  |  |  |  |  |  |  |  |  |  |  |  |
Change in valuation allowance |  |  |  |  |  |  |  |  |  |  | 63.6 | (31.0) | 42.6
Non-U.S. earnings, net of foreign taxes |  |  |  |  |  |  |  |  |  |  | 27.1 | (2.9) | 21.5
State taxes |  |  |  |  |  |  |  |  |  |  | (17.5) | 4.0 | 0.6
Tax rate changes |  |  |  |  |  |  |  |  |  |  | (5.7) | 1.7 | (44.3)
Member’s surplus contributions |  |  |  |  |  |  |  |  |  |  | (3.6) | (2.6) | (3.0)
Withholding tax |  |  |  |  |  |  |  |  |  |  | (1.6) | (2.7) | (2.0)
Tax exempt interest and dividends |  |  |  |  |  |  |  |  |  |  | 1.1 | 0.6 | 0.5
Tax reserve adjustments |  |  |  |  |  |  |  |  |  |  | (0.7) | (0.8) | (0.3)
Officer compensation |  |  |  |  |  |  |  |  |  |  | 0.0 | 0.0 | (4.1)
Other, net |  |  |  |  |  |  |  |  |  |  | (6.9) | 0.3 | (1.0)
Total income tax (expense) benefit |  |  | $ (10.4) | $ (8.8) | $ 0.1 | $ (10.2) | $ 3.6 | $ 3.6 | $ (2.5) | $ (0.7) | (29.3) | 4.0 | 7.8
Pre-tax income (loss) |  |  | $ 56.5 | $ 51.1 | $ 15.8 | $ 281.7 | $ (144.1) | $ 44.3 | $ (12.4) | $ (66.0) | 405.1 | (178.2) | 7.8
Tax Payments and Receipts |  |  |  |  |  |  |  |  |  |  |  |  |
Net income tax payments to (receipts from) national governments, total |  |  |  |  |  |  |  |  |  |  | 3.7 | 3.5 | 2.0
Non-US |  |  |  |  |  |  |  |  |  |  |  |  |
Differences in taxes resulting from: |  |  |  |  |  |  |  |  |  |  |  |  |
Pre-tax income (loss) |  |  |  |  |  |  |  |  |  |  | $ 100.4 | $ (30.1) | $ 71.3

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