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Income Taxes - Effective Rate Reconciliation (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Income Tax Disclosure [Abstract] |  |  |
Tax (expense) benefit at the U.S. statutory rate | $ (118.7) | $ 31.4 | $ 57.5
Differences in taxes resulting from: |  |  |
Non-U.S. earnings, net of foreign taxes | 103.7 | (41.2) | (78.2)
Bermuda corporate income tax | 68.0 | 0.0 | 0.0
Change in valuation allowance | (30.2) | (19.6) | (2.0)
State taxes | (8.2) | (2.8) | (7.3)
Noncontrolling interest | 6.8 | 3.4 | 2.1
Member’s surplus contributions | (5.7) | (6.2) | (5.6)
Withholding tax | (4.1) | (3.1) | (0.3)
Tax rate changes | (0.6) | (0.4) | (10.9)
Officer compensation | (0.2) | (1.0) | (1.5)
Tax exempt interest and dividends | 0.2 | 0.2 | 0.2
Other, net | 4.5 | (2.1) | 1.6
Total income tax (expense) benefit | $ 15.5 | $ (41.4) | $ (44.4)

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