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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, 2023 | Mar. 31, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | $ 1,676 | $ 1,578
Reported in Net investment gains (losses) | $ 0 | $ 0
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 (loss) | Other comprehensive income (loss)
Reported in Other comprehensive income (loss) | $ 32 | $ (108)
Total realized and unrealized investment gains (losses) | 31 | (103)
Purchases | 136 | 219
Sales | 0 | (5)
Settlements | (12) | (39)
Transfers into Level 3 | 23 | 15
Transfers out of Level 3 | (10) | (51)
Balance, Ending, Assets | 1,844 | 1,614
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (6) | 3
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 32 | (108)
Corporate and other bonds |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 810 | 937
Reported in Net investment gains (losses) | 0 | (1)
Reported in Other comprehensive income (loss) | 24 | (71)
Total realized and unrealized investment gains (losses) | 24 | (72)
Purchases | 81 | 67
Sales | 0 | (5)
Settlements | (3) | (22)
Transfers into Level 3 | 0 | 10
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 912 | 915
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 | 24 | (72)
States, municipalities and political subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 43 | 56
Reported in Net investment gains (losses) | 0 | 0
Reported in Other comprehensive income (loss) | 1 | (5)
Total realized and unrealized investment gains (losses) | 1 | (5)
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 | 51
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)
Asset-backed |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 788 | 556
Reported in Net investment gains (losses) | 0 | 2
Reported in Other comprehensive income (loss) | 7 | (32)
Total realized and unrealized investment gains (losses) | 12 | (29)
Purchases | 55 | 140
Sales | 0 | 0
Settlements | (9) | (17)
Transfers into Level 3 | 23 | 5
Transfers out of Level 3 | (10) | (51)
Balance, Ending, Assets | 859 | 604
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 | 7 | (31)
Equity securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 35 | 29
Reported in Net investment gains (losses) | 0 | (1)
Reported in Other comprehensive income (loss) | 0 | 0
Total realized and unrealized investment gains (losses) | (6) | 3
Purchases | 0 | 12
Sales | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 29 | 44
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (6) | 3
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 | (1) | 5
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 | 5 | 1
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 | $ (6) | $ 4

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