v3.25.2
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 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Balance, Beginning, Assets $ 2,301 $ 2,007 $ 2,216 $ 2,014
Reported in Net investment gains (losses) $ (3) $ (3) $ (1) $ (7)
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 income Other comprehensive income Other comprehensive income Other comprehensive income
Reported in Other comprehensive income (loss) $ 12 $ (19) $ 36 $ (37)
Total realized and unrealized investment gains (losses) 14 (17) 43 (27)
Purchases 66 130 148 222
Sales (7) (5) (7) (33)
Settlements (46) (42) (87) (95)
Transfers into Level 3 0 0 15 11
Transfers out of Level 3 0 0 0 (19)
Balance, Ending, Assets 2,328 2,073 2,328 2,073
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period (1) 0 (1) 2
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period 12 (19) 36 (39)
Corporate and other bonds        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Balance, Beginning, Assets 1,351 1,082 1,278 1,045
Reported in Net investment gains (losses) 1 0 1 0
Reported in Other comprehensive income (loss) 16 (8) 37 (20)
Total realized and unrealized investment gains (losses) 17 (8) 38 (20)
Purchases 44 72 99 146
Sales 0 0 0 0
Settlements (24) (17) (42) (53)
Transfers into Level 3 0 0 15 11
Transfers out of Level 3 0 0 0 0
Balance, Ending, Assets 1,388 1,129 1,388 1,129
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 16 (8) 37 (22)
States, municipalities and political subdivisions        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Balance, Beginning, Assets 44 43 42 44
Reported in Net investment gains (losses) 0 0 0 0
Reported in Other comprehensive income (loss) 0 0 2 (1)
Total realized and unrealized investment gains (losses) 0 0 2 (1)
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 44 43 44 43
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 2 (1)
Asset-backed        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Balance, Beginning, Assets 889 871 876 901
Reported in Net investment gains (losses) (4) (3) (4) (7)
Reported in Other comprehensive income (loss) (4) (11) (3) (16)
Total realized and unrealized investment gains (losses) (3) (9) 2 (12)
Purchases 22 55 49 73
Sales 0 (5) 0 (14)
Settlements (22) (25) (41) (42)
Transfers into Level 3 0 0 0 0
Transfers out of Level 3 0 0 0 (19)
Balance, Ending, Assets 886 887 886 887
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 (4) (11) (3) (16)
Equity securities        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Balance, Beginning, Assets 17 11 20 24
Reported in Net investment gains (losses) 0 0 2 0
Reported in Other comprehensive income (loss) 0 0 0 0
Total realized and unrealized investment gains (losses) 0 0 1 6
Purchases 0 3 0 3
Sales (7) 0 (7) (19)
Settlements 0 0 (4) 0
Transfers into Level 3 0 0 0 0
Transfers out of Level 3 0 0 0 0
Balance, Ending, Assets 10 14 10 14
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period (1) 0 (1) 2
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 5 5 8 17
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 5 5 9 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 $ 0 $ 0 $ (1) $ 6