v3.25.4
FAIR VALUE - Schedule of Fair Value Measurement Levels for all Assets and Liabilities (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value $ 34,573 $ 28,908
Equity securities, fair value 180 217
Fixed maturities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 2,500 2,200
U.S. government agencies and corporations    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 830 669
Obligations of U.S. States and political subdivisions    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 41 70
Corporate securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 9,882 7,010
Asset-backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 5,077 5,982
Agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 412 0
Non-agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 1,121 900
Agency residential    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 5,465 4,931
Non-agency residential    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 1,721 1,289
Foreign government securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 2,371 2,196
Foreign corporate securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 7,653 5,861
Agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value   900
Quoted Prices in Active Markets for Identical Assets (Level 1)    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Equity securities, fair value 88 79
Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. government agencies and corporations    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Obligations of U.S. States and political subdivisions    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Asset-backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0  
Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0  
Quoted Prices in Active Markets for Identical Assets (Level 1) | Agency residential    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-agency residential    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign government securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign corporate securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value   0
Significant Other Observable Inputs (Level 2)    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 32,099 26,719
Equity securities, fair value 92 133
Significant Other Observable Inputs (Level 2) | U.S. government agencies and corporations    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 830 669
Significant Other Observable Inputs (Level 2) | Obligations of U.S. States and political subdivisions    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 41 70
Significant Other Observable Inputs (Level 2) | Corporate securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 9,512 6,492
Significant Other Observable Inputs (Level 2) | Asset-backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 2,987 4,325
Significant Other Observable Inputs (Level 2) | Agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 412  
Significant Other Observable Inputs (Level 2) | Non-agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 1,121  
Significant Other Observable Inputs (Level 2) | Agency residential    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 5,465 4,931
Significant Other Observable Inputs (Level 2) | Non-agency residential    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 1,721 1,289
Significant Other Observable Inputs (Level 2) | Foreign government securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 2,371 2,196
Significant Other Observable Inputs (Level 2) | Foreign corporate securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 7,639 5,847
Significant Other Observable Inputs (Level 2) | Agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value   900
Significant Unobservable Inputs (Level 3)    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 2,474 2,189
Equity securities, fair value 0 5
Significant Unobservable Inputs (Level 3) | U.S. government agencies and corporations    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Significant Unobservable Inputs (Level 3) | Obligations of U.S. States and political subdivisions    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Significant Unobservable Inputs (Level 3) | Corporate securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 370 518
Significant Unobservable Inputs (Level 3) | Asset-backed securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 2,091 1,657
Significant Unobservable Inputs (Level 3) | Agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0  
Significant Unobservable Inputs (Level 3) | Non-agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0  
Significant Unobservable Inputs (Level 3) | Agency residential    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Significant Unobservable Inputs (Level 3) | Non-agency residential    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Significant Unobservable Inputs (Level 3) | Foreign government securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value 0 0
Significant Unobservable Inputs (Level 3) | Foreign corporate securities    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value $ 14 14
Significant Unobservable Inputs (Level 3) | Agency commercial    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Fair Value   $ 0