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Income Taxes - Effective Tax Rate Reconciliation and Pretax Income (Loss) and Revenue by Tax Jurisdiction (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Pre-tax Income Taxes and Revenue [Line Items] |  |  |
Expected tax provision (benefit) | $ 82 | $ 122 | $ 23
Tax-exempt interest | (10) | (15) | (14)
Return to provision adjustment | (1) | (6) | (20)
Noncontrolling interest | (3) | (5) | (3)
State taxes, net of federal benefit | 13 | (10) | 12
Foreign taxes | 5 | 11 | 6
Stock based compensation | 1 | 2 | 5
Bermuda ETA | (1) | (189) | 0
Global minimum tax | 13 | 0 | 0
Other | (3) | (3) | 2
Total provision (benefit) for income taxes | $ 96 | $ (93) | $ 11
Effective tax rate | 19.70% | (13.90%) | 7.20%
Total | $ 488 | $ 668 | $ 148
Total revenues | 872 | 1,373 | 723
U.S. |  |  |
Pre-tax Income Taxes and Revenue [Line Items] |  |  |
Total | 445 | 622 | 189
Total revenues | 720 | 1,169 | 661
Bermuda |  |  |
Pre-tax Income Taxes and Revenue [Line Items] |  |  |
Total | 90 | 79 | 44
Total revenues | 130 | 165 | 84
U.K. |  |  |
Pre-tax Income Taxes and Revenue [Line Items] |  |  |
Total | (33) | (25) | (69)
Total revenues | 23 | 37 | (15)
France |  |  |
Pre-tax Income Taxes and Revenue [Line Items] |  |  |
Total | (14) | (8) | (16)
Total revenues | (1) | 2 | (8)
Other |  |  |
Pre-tax Income Taxes and Revenue [Line Items] |  |  |
Total revenues | $ 0 | $ 0 | $ 1

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