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Income Taxes - Reconciliation of effective tax rate (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Income Tax Disclosure [Abstract] |  |  |
Expected income tax expense (benefit) computed on pre-tax income at weighted average income tax rate | $ 424 | $ 300 | $ 110
Addition (reduction) in income tax expense (benefit) resulting from: |  |  |
Sale of subsidiaries/Bargain purchase option | (45) | 0 | 0
Investment income | (39) | (14) | (13)
Change in tax rate | 12 | (1,179) | (5)
Share based compensation | (11) | (13) | (9)
Tax credits | (5) | (3) | (10)
Base eroding tax/Alternative minimum tax | 5 | 9 | 8
State taxes, net of U.S. federal tax benefit | 4 | 6 | 11
Change in valuation allowance | 3 | 4 | (23)
Uncertain tax position | 3 | 0 | 0
Dividend withholding taxes | 3 | 9 | 11
Other | 8 | 8 | 0
Income tax expense (benefit) | $ 362 | $ (873) | $ 80

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