v3.25.2
FAIR VALUE - Narrative (Details) - USD ($)
1 Months Ended 3 Months Ended 6 Months Ended
Dec. 31, 2015
Jun. 30, 2025
Jun. 30, 2025
Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Fair value   $ 19,796,000,000 $ 19,796,000,000 $ 17,186,000,000
Annual dividend rate 1.75%      
Transfers in/(out) of Level 3 and reclassification of securities in/(out) of investment categories   0 0  
Other invested assets, at fair value   1,618,000,000 1,618,000,000 1,523,000,000
Fair Value | Investments        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Other invested assets, at fair value   $ 251,000,000 $ 251,000,000 239,000,000
4.868% Senior notes | Senior Notes        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Observable input constant maturity     10 years  
Other invested assets, at fair value   4.868% 4.868%  
Redeemable Convertible Preferred Stock        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Preferred stock term     25 years  
Annual dividend rate     1.75%  
Fixed maturities        
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]        
Fair value   $ 2,300,000,000 $ 2,300,000,000 $ 2,200,000,000