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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, 2024 | Dec. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | $ 2,014 | $ 1,676
Reported in Net investment gains (losses) | $ (13) | $ (4)
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) | $ (29) | $ 48
Total realized and unrealized investment gains (losses) | (9) | 57
Purchases | 480 | 467
Sales | (43) | (4)
Settlements | (187) | (97)
Transfers into Level 3 | 11 | 34
Transfers out of Level 3 | (50) | (119)
Balance, Ending, Assets | 2,216 | 2,014
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 7 | (7)
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | (35) | 48
Corporate and other bonds |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 1,045 | 810
Reported in Net investment gains (losses) | (1) | 0
Reported in Other comprehensive income (loss) | (15) | 38
Total realized and unrealized investment gains (losses) | (16) | 38
Purchases | 352 | 219
Sales | (10) | 0
Settlements | (104) | (33)
Transfers into Level 3 | 11 | 11
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 1,278 | 1,045
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | (1) | 0
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period | (21) | 38
States, municipalities and political subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 44 | 43
Reported in Net investment gains (losses) | 0 | 0
Reported in Other comprehensive income (loss) | (2) | 1
Total realized and unrealized investment gains (losses) | (2) | 1
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 | 42 | 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 | (2) | 1
Asset-backed |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 901 | 788
Reported in Net investment gains (losses) | (12) | (4)
Reported in Other comprehensive income (loss) | (12) | 9
Total realized and unrealized investment gains (losses) | (3) | 25
Purchases | 125 | 248
Sales | (14) | 0
Settlements | (83) | (64)
Transfers into Level 3 | 0 | 23
Transfers out of Level 3 | (50) | (119)
Balance, Ending, Assets | 876 | 901
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 | (12) | 9
Equity securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance, Beginning, Assets | 24 | 35
Reported in Net investment gains (losses) | 0 | 0
Reported in Other comprehensive income (loss) | 0 | 0
Total realized and unrealized investment gains (losses) | 12 | (7)
Purchases | 3 | 0
Sales | (19) | (4)
Settlements | 0 | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Balance, Ending, Assets | 20 | 24
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period | 8 | (7)
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 | 33 | 13
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 | 21 | 20
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 | $ 12 | $ (7)

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- Definition Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 101 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482078/820-10-55-101 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-3 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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