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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, 2022 | Mar. 31, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | $ 1,578 | $ 1,151
Reported in Other comprehensive income (loss) | (108) | (51)
Total realized and unrealized investment gains (losses) | (103) | (60)
Purchases | 219 | 72
Sales | (5) | 0
Settlements | (39) | (19)
Transfers into Level 3 | 15 | 19
Transfers out of Level 3 | (51) | (8)
Balance, Ending, Assets | 1,614 | 1,155
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 3 | 2
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | (108) | (51)
Corporate and other bonds |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 937 | 770
Reported in Other comprehensive income (loss) | (71) | (40)
Total realized and unrealized investment gains (losses) | (72) | (53)
Purchases | 67 | 42
Sales | (5) | 0
Settlements | (22) | (2)
Transfers into Level 3 | 10 | 10
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 915 | 767
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 | (72) | (40)
States, municipalities and political subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 56 | 46
Reported in Other comprehensive income (loss) | (5) | (2)
Total realized and unrealized investment gains (losses) | (5) | (2)
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 | 51 | 44
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 | (5) | (2)
Asset-backed |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 556 | 308
Reported in Other comprehensive income (loss) | (32) | (9)
Total realized and unrealized investment gains (losses) | (29) | (7)
Purchases | 140 | 30
Sales | 0 | 0
Settlements | (17) | (17)
Transfers into Level 3 | 5 | 9
Transfers out of Level 3 | (51) | (8)
Balance, Ending, Assets | 604 | 315
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 | (31) | (9)
Equity securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 29 | 27
Reported in Other comprehensive income (loss) | 0 | 0
Total realized and unrealized investment gains (losses) | 3 | 2
Purchases | 12 | 0
Sales | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 44 | 29
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 3 | 2
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 0 | 0
Reported in Net investment gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment gains (losses) | 0 | (12)
Reported in Net investment gains (losses) | Corporate and other bonds |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment gains (losses) | (1) | (13)
Reported in Net investment gains (losses) | States, municipalities and political subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment gains (losses) | 0 | 0
Reported in Net investment gains (losses) | Asset-backed |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment gains (losses) | 2 | 0
Reported in Net investment gains (losses) | Equity securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment gains (losses) | (1) | 1
Reported in Net investment income |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment income | 5 | 3
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 | 1 | 2
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 | $ 4 | $ 1

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