v3.26.1
FAIR VALUE - Schedule of Activity Under Level 3, Fair Value Measurements Using Significant Unobservable Inputs by Asset Type (Details) - USD ($)
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Total gains or (losses) (realized/unrealized)        
Transfers in/(out) of Level 3 and reclassification of securities in/(out) of investment categories $ 0 $ 0 $ 0 $ 0
Market Value        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance of fixed maturities 2,568,000,000 2,234,000,000 2,474,000,000 2,189,000,000
Total gains or (losses) (realized/unrealized)        
Included in earnings (13,000,000) (1,000,000) (15,000,000) (1,000,000)
Included in other comprehensive income (loss) (1,000,000) (12,000,000) (3,000,000) (17,000,000)
Purchases, issuances and settlements 253,000,000 91,000,000 350,000,000 140,000,000
Transfers in/(out) of Level 3 and reclassification of securities in/(out) of investment categories 0 0 0 0
Ending balance of fixed maturities 2,806,000,000 2,312,000,000 2,806,000,000 2,312,000,000
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date (13,000,000) (2,000,000) (14,000,000) (2,000,000)
Corporate securities | Market Value        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance of fixed maturities 364,000,000 468,000,000 370,000,000 518,000,000
Total gains or (losses) (realized/unrealized)        
Included in earnings (1,000,000) (1,000,000) (3,000,000) (1,000,000)
Included in other comprehensive income (loss) 0 (8,000,000) 2,000,000 (15,000,000)
Purchases, issuances and settlements 2,000,000 (22,000,000) (4,000,000) (67,000,000)
Transfers in/(out) of Level 3 and reclassification of securities in/(out) of investment categories 0 0 0 0
Ending balance of fixed maturities 365,000,000 436,000,000 365,000,000 436,000,000
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date (1,000,000) (2,000,000) (2,000,000) (2,000,000)
Asset-backed securities | Market Value        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance of fixed maturities 2,190,000,000 1,752,000,000 2,091,000,000 1,657,000,000
Total gains or (losses) (realized/unrealized)        
Included in earnings (12,000,000) 0 (12,000,000) 0
Included in other comprehensive income (loss) (1,000,000) (3,000,000) (5,000,000) (2,000,000)
Purchases, issuances and settlements 250,000,000 114,000,000 353,000,000 207,000,000
Transfers in/(out) of Level 3 and reclassification of securities in/(out) of investment categories 0 0 0 0
Ending balance of fixed maturities 2,428,000,000 1,862,000,000 2,428,000,000 1,862,000,000
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date (12,000,000) 0 (12,000,000) 0
Foreign corporate securities | Market Value        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance of fixed maturities 14,000,000 14,000,000 14,000,000 14,000,000
Total gains or (losses) (realized/unrealized)        
Included in earnings 0 0 0 0
Included in other comprehensive income (loss) 0 0 0 0
Purchases, issuances and settlements 0 0 0 0
Transfers in/(out) of Level 3 and reclassification of securities in/(out) of investment categories 0 0 0 0
Ending balance of fixed maturities 13,000,000 14,000,000 13,000,000 14,000,000
The amount of total gains or losses for the period included in earnings (or changes in net assets) attributable to the change in unrealized gains or losses relating to assets still held at the reporting date $ 0 $ 0 $ 0 $ 0