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Fair Value (Table of reconciliation for assets and liabilities measured at fair value on a recurring basis using significant unobservable inputs) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | $ 2,216 | $ 2,014
Reported in Net investment gains (losses) | $ 2 | $ (4)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net investment losses | Net investment losses
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration] | Other comprehensive income | Other comprehensive income
Reported in Other comprehensive income (loss) | $ 24 | $ (18)
Total realized and unrealized investment gains (losses) | 29 | (10)
Purchases | 82 | 92
Sales | 0 | (28)
Settlements | (41) | (53)
Transfers into Level 3 | 15 | 11
Transfers out of Level 3 | 0 | (19)
Balance, Ending, Assets | 2,301 | 2,007
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (1) | 1
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 24 | (20)
Corporate and other bonds |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 1,278 | 1,045
Reported in Net investment gains (losses) | 0 | 0
Reported in Other comprehensive income (loss) | 21 | (12)
Total realized and unrealized investment gains (losses) | 21 | (12)
Purchases | 55 | 74
Sales | 0 | 0
Settlements | (18) | (36)
Transfers into Level 3 | 15 | 11
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 1,351 | 1,082
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 0 | 0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 21 | (14)
States, municipalities and political subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 42 | 44
Reported in Net investment gains (losses) | 0 | 0
Reported in Other comprehensive income (loss) | 2 | (1)
Total realized and unrealized investment gains (losses) | 2 | (1)
Purchases | 0 | 0
Sales | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 44 | 43
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 0 | 0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 2 | (1)
Asset-backed |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 876 | 901
Reported in Net investment gains (losses) | 0 | (4)
Reported in Other comprehensive income (loss) | 1 | (5)
Total realized and unrealized investment gains (losses) | 5 | (3)
Purchases | 27 | 18
Sales | 0 | (9)
Settlements | (19) | (17)
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | (19)
Balance, Ending, Assets | 889 | 871
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 0 | 0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 1 | (5)
Equity securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 20 | 24
Reported in Net investment gains (losses) | 2 | 0
Reported in Other comprehensive income (loss) | 0 | 0
Total realized and unrealized investment gains (losses) | 1 | 6
Purchases | 0 | 0
Sales | 0 | (19)
Settlements | (4) | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 17 | 11
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (1) | 1
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 0 | 0
Reported in Net investment income |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment income | 3 | 12
Reported in Net investment income | Corporate and other bonds |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment income | 0 | 0
Reported in Net investment income | States, municipalities and political subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment income | 0 | 0
Reported in Net investment income | Asset-backed |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment income | 4 | 6
Reported in Net investment income | Equity securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment income | $ (1) | $ 6

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