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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 | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | $ 1,151 | $ 651
Reported in Other comprehensive income (loss) | (43) | 60
Total realized and unrealized investment gains (losses) | (46) | 56
Purchases | 612 | 478
Sales | (32) | (12)
Settlements | (130) | (45)
Transfers into Level 3 | 150 | 40
Transfers out of Level 3 | (127) | (17)
Balance, Ending, Assets | 1,578 | 1,151
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (2) | (6)
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | (44) | 62
Corporate and other bonds |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 770 | 468
Reported in Other comprehensive income (loss) | (32) | 43
Total realized and unrealized investment gains (losses) | (42) | 44
Purchases | 312 | 264
Sales | (3) | (3)
Settlements | (68) | (13)
Transfers into Level 3 | 20 | 10
Transfers out of Level 3 | (52) | 0
Balance, Ending, Assets | 937 | 770
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 | (32) | 43
States, municipalities and political subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 46 | 0
Reported in Other comprehensive income (loss) | (1) | 1
Total realized and unrealized investment gains (losses) | (1) | 1
Purchases | 12 | 45
Sales | 0 | 0
Settlements | (1) | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 56 | 46
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) | 1
Asset-backed |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 308 | 165
Reported in Other comprehensive income (loss) | (10) | 16
Total realized and unrealized investment gains (losses) | (3) | 17
Purchases | 287 | 154
Sales | (9) | (9)
Settlements | (61) | (32)
Transfers into Level 3 | 109 | 30
Transfers out of Level 3 | (75) | (17)
Balance, Ending, Assets | 556 | 308
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 | (11) | 18
Equity securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 27 | 18
Reported in Other comprehensive income (loss) | 0 | 0
Total realized and unrealized investment gains (losses) | 0 | (6)
Purchases | 1 | 15
Sales | (20) | 0
Settlements | 0 | 0
Transfers into Level 3 | 21 | 0
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 29 | 27
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (2) | (6)
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) | (12) | (4)
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) | (10) | 1
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) | 0 | (1)
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) | (2) | (4)
Reported in Net investment income |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Reported in Net investment income | 9 | 0
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 | 7 | 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 | $ 2 | $ (2)

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