v3.25.1
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
Mar. 31, 2025
Mar. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, Beginning, Assets $ 2,216 $ 2,014
Reported in Net investment gains (losses) $ 2 $ (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 Other comprehensive income
Reported in Other comprehensive income (loss) $ 24 $ (18)
Total realized and unrealized investment gains (losses) 29 (10)
Purchases 82 92
Sales 0 (28)
Settlements (41) (53)
Transfers into Level 3 15 11
Transfers out of Level 3 0 (19)
Balance, Ending, Assets 2,301 2,007
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period (1) 1
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Other comprehensive income (loss) in the period 24 (20)
Corporate and other bonds    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, Beginning, Assets 1,278 1,045
Reported in Net investment gains (losses) 0 0
Reported in Other comprehensive income (loss) 21 (12)
Total realized and unrealized investment gains (losses) 21 (12)
Purchases 55 74
Sales 0 0
Settlements (18) (36)
Transfers into Level 3 15 11
Transfers out of Level 3 0 0
Balance, Ending, Assets 1,351 1,082
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 21 (14)
States, municipalities and political subdivisions    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, Beginning, Assets 42 44
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 44 43
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 876 901
Reported in Net investment gains (losses) 0 (4)
Reported in Other comprehensive income (loss) 1 (5)
Total realized and unrealized investment gains (losses) 5 (3)
Purchases 27 18
Sales 0 (9)
Settlements (19) (17)
Transfers into Level 3 0 0
Transfers out of Level 3 0 (19)
Balance, Ending, Assets 889 871
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 (5)
Equity securities    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, Beginning, Assets 20 24
Reported in Net investment gains (losses) 2 0
Reported in Other comprehensive income (loss) 0 0
Total realized and unrealized investment gains (losses) 1 6
Purchases 0 0
Sales 0 (19)
Settlements (4) 0
Transfers into Level 3 0 0
Transfers out of Level 3 0 0
Balance, Ending, Assets 17 11
Unrealized gains (losses) on Level 3 assets and liabilities recognized in Net income (loss) in the period (1) 1
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 3 12
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 4 6
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) $ 6