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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, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | $ 1,923 | $ 1,580 | $ 1,676 | $ 1,578
Reported in Net investment gains (losses) | $ (4) | $ (1) | $ (5) | $ (1)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net investment losses | Net investment losses | 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 loss | Other comprehensive loss | Other comprehensive loss | Other comprehensive loss
Reported in Other comprehensive income (loss) | $ (66) | $ (92) | $ (57) | $ (339)
Total realized and unrealized investment gains (losses) | (66) | (91) | (55) | (329)
Purchases | 90 | 125 | 381 | 487
Sales | (2) | 0 | (4) | (10)
Settlements | (32) | (18) | (66) | (108)
Transfers into Level 3 | 0 | 47 | 34 | 76
Transfers out of Level 3 | (7) | (53) | (60) | (104)
Balance, Ending, Assets | 1,906 | 1,590 | 1,906 | 1,590
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (1) | (7) | (8) | (8)
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | (66) | (93) | (57) | (338)
Corporate and other bonds |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | 971 | 846 | 810 | 937
Reported in Net investment gains (losses) | 0 | 0 | 0 | (2)
Reported in Other comprehensive income (loss) | (36) | (50) | (27) | (203)
Total realized and unrealized investment gains (losses) | (36) | (49) | (27) | (204)
Purchases | 29 | 9 | 178 | 127
Sales | 0 | 0 | 0 | (5)
Settlements | (19) | (4) | (27) | (63)
Transfers into Level 3 | 0 | 0 | 11 | 10
Transfers out of Level 3 | 0 | 0 | 0 | 0
Balance, Ending, Assets | 945 | 802 | 945 | 802
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 | (36) | (51) | (27) | (203)
States, municipalities and political subdivisions |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | 43 | 46 | 43 | 56
Reported in Net investment gains (losses) | 0 | 0 | 0 | 0
Reported in Other comprehensive income (loss) | (2) | (4) | (2) | (14)
Total realized and unrealized investment gains (losses) | (2) | (4) | (2) | (14)
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Settlements | 0 | 0 | 0 | 0
Transfers into Level 3 | 0 | 0 | 0 | 0
Transfers out of Level 3 | 0 | 0 | 0 | 0
Balance, Ending, Assets | 41 | 42 | 41 | 42
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) | (4) | (2) | (14)
Asset-backed |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | 883 | 641 | 788 | 556
Reported in Net investment gains (losses) | (4) | 2 | (5) | 7
Reported in Other comprehensive income (loss) | (28) | (38) | (28) | (122)
Total realized and unrealized investment gains (losses) | (27) | (31) | (18) | (104)
Purchases | 61 | 116 | 203 | 348
Sales | 0 | 0 | 0 | (2)
Settlements | (13) | (14) | (39) | (54)
Transfers into Level 3 | 0 | 47 | 23 | 66
Transfers out of Level 3 | (7) | (43) | (60) | (94)
Balance, Ending, Assets | 897 | 716 | 897 | 716
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 | (28) | (38) | (28) | (121)
Equity securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance, Beginning, Assets | 26 | 47 | 35 | 29
Reported in Net investment gains (losses) | 0 | (3) | 0 | (6)
Reported in Other comprehensive income (loss) | 0 | 0 | 0 | 0
Total realized and unrealized investment gains (losses) | (1) | (7) | (8) | (7)
Purchases | 0 | 0 | 0 | 12
Sales | (2) | 0 | (4) | (3)
Settlements | 0 | 0 | 0 | 9
Transfers into Level 3 | 0 | 0 | 0 | 0
Transfers out of Level 3 | 0 | (10) | 0 | (10)
Balance, Ending, Assets | 23 | 30 | 23 | 30
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (1) | (7) | (8) | (8)
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 income |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Reported in Net investment income | 4 | 2 | 7 | 11
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 | 1 | 0 | 1
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 | 5 | 5 | 15 | 11
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) | $ (4) | $ (8) | $ (1)

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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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