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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 | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | $ 1,375 | $ 788 | $ 1,151 | $ 651
Reported in Other comprehensive income (loss) | 2 | 14 | (27) | 45
Total realized and unrealized investment gains (losses) | 2 | 14 | (32) | 38
Purchases | 139 | 206 | 429 | 357
Sales | (20) | 0 | (27) | (9)
Settlements | (22) | (17) | (74) | (31)
Transfers into Level 3 | 52 | 8 | 92 | 8
Transfers out of Level 3 | (90) | (2) | (103) | (17)
Balance, Ending, Assets | 1,436 | 997 | 1,436 | 997
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (3) | 0 | (1) | (7)
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 2 | 13 | (27) | 48
Corporate and other bonds |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | 883 | 555 | 770 | 468
Reported in Other comprehensive income (loss) | 1 | 5 | (23) | 27
Total realized and unrealized investment gains (losses) | 2 | 5 | (32) | 27
Purchases | 55 | 129 | 219 | 200
Sales | 0 | 0 | (3) | 0
Settlements | (11) | (3) | (35) | (9)
Transfers into Level 3 | 0 | 8 | 10 | 8
Transfers out of Level 3 | (52) | 0 | (52) | 0
Balance, Ending, Assets | 877 | 694 | 877 | 694
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 0 | 0 | 0 | 0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 2 | 5 | (22) | 29
States, municipalities and political subdivisions |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | 57 | 0 | 46 | 0
Reported in Other comprehensive income (loss) | 0 | 0 | 0 | 0
Total realized and unrealized investment gains (losses) | 0 | 0 | 0 | 0
Purchases | 0 | 45 | 12 | 45
Sales | 0 | 0 | 0 | 0
Settlements | 0 | 0 | (1) | 0
Transfers into Level 3 | 0 | 0 | 0 | 0
Transfers out of Level 3 | 0 | 0 | 0 | 0
Balance, Ending, Assets | 57 | 45 | 57 | 45
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 0 | 0 | 0 | 0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 0 | 0 | 0 | 0
Asset-backed |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | 410 | 222 | 308 | 165
Reported in Other comprehensive income (loss) | 1 | 9 | (4) | 18
Total realized and unrealized investment gains (losses) | 2 | 9 | 0 | 18
Purchases | 83 | 20 | 197 | 100
Sales | (9) | 0 | (9) | (9)
Settlements | (11) | (14) | (38) | (22)
Transfers into Level 3 | 41 | 0 | 71 | 0
Transfers out of Level 3 | (38) | (2) | (51) | (17)
Balance, Ending, Assets | 478 | 235 | 478 | 235
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 0 | 0 | 0 | 0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 0 | 8 | (5) | 19
Equity securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | 25 | 11 | 27 | 18
Reported in Other comprehensive income (loss) | 0 | 0 | 0 | 0
Total realized and unrealized investment gains (losses) | (2) | 0 | 0 | (7)
Purchases | 1 | 12 | 1 | 12
Sales | (11) | 0 | (15) | 0
Settlements | 0 | 0 | 0 | 0
Transfers into Level 3 | 11 | 0 | 11 | 0
Transfers out of Level 3 | 0 | 0 | 0 | 0
Balance, Ending, Assets | 24 | 23 | 24 | 23
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (3) | 0 | (1) | (7)
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | 0 | 0 | 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) | (2) | 0 | (11) | (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) | 1 | 0 | (9) | 0
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 | 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 | 0 | 0 | 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) | (3) | 0 | (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 | 2 | 0 | 6 | (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 | 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 | 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 | 0 | 4 | 0
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 | $ 0 | $ 2 | $ (3)

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