v3.24.1.u1
Future Policy Benefits - Schedule of liabilities by product (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2024
Mar. 31, 2023
Dec. 31, 2023
Dec. 31, 2022
Liability for Future Policy Benefit, Activity [Line Items]        
Net liability for future policy benefits, beginning balance $ 57,108      
Effect of actual variances from expected experience     $ (13) $ 16
Adjusted beginning of year balance     15,152 14,599
Interest accrual 128 $ 118    
Other (4) 3    
Net liability for future policy benefits, end of period 57,587 53,406    
Less: Reinsurance recoverable: (22,107) (23,491)    
Net liability for future policy benefits after reinsurance recoverable 35,480 29,915    
Universal Life        
Liability for Future Policy Benefit, Activity [Line Items]        
Net liability for future policy benefits, beginning balance 3,786 3,355    
Effect of actual variances from expected experience     108 73
Adjusted beginning of year balance     3,894 3,428
Assessments 145 179    
Excess benefits paid (232) (238)    
Interest accrual 39 29    
Other 0 (5)    
Changes related to unrealized appreciation (depreciation) of investments 126 119    
Net liability for future policy benefits, end of period 3,972 3,512    
Less: Reinsurance recoverable: (227) (192)    
Net liability for future policy benefits after reinsurance recoverable 3,745 3,320    
Life Insurance        
Liability for Future Policy Benefit, Activity [Line Items]        
Effect of actual variances from expected experience     (13) 12
Adjusted beginning of year balance     14,135 13,538
Interest accrual 117 106    
Other (4) 3    
Net liability for future policy benefits, end of period 13,346 13,807    
Less: Reinsurance recoverable: (714) (1,187)    
Net liability for future policy benefits after reinsurance recoverable $ 12,632 $ 12,620    
Weighted average liability duration of the liability for future policy benefits (in years) 12 years 7 months 6 days 12 years 4 months 24 days    
Life Insurance | Universal Life        
Liability for Future Policy Benefit, Activity [Line Items]        
Net liability for future policy benefits, beginning balance $ 3,731 $ 3,300    
Effect of actual variances from expected experience     109 74
Adjusted beginning of year balance     3,840 3,374
Assessments 145 179    
Excess benefits paid (232) (238)    
Interest accrual 38 28    
Other 0 (5)    
Changes related to unrealized appreciation (depreciation) of investments 126 119    
Net liability for future policy benefits, end of period 3,917 3,457    
Less: Reinsurance recoverable: (172) (192)    
Net liability for future policy benefits after reinsurance recoverable $ 3,745 $ 3,265    
Weighted average liability duration of the liability for future policy benefits (in years) 25 years 3 months 18 days 26 years 4 months 24 days    
Corporate and Other        
Liability for Future Policy Benefit, Activity [Line Items]        
Effect of actual variances from expected experience     0 3
Adjusted beginning of year balance     1,017 1,060
Interest accrual $ 11 $ 12    
Other 0 0    
Net liability for future policy benefits, end of period 21,352 22,263    
Less: Reinsurance recoverable: (21,352) (22,263)    
Net liability for future policy benefits after reinsurance recoverable $ 0 $ 0    
Weighted average liability duration of the liability for future policy benefits (in years) 11 years 2 months 12 days 11 years 7 months 6 days    
Corporate and Other | Universal Life        
Liability for Future Policy Benefit, Activity [Line Items]        
Net liability for future policy benefits, beginning balance $ 55 $ 55    
Effect of actual variances from expected experience     (1) (1)
Adjusted beginning of year balance     $ 54 $ 54
Assessments 0 0    
Excess benefits paid 0 0    
Interest accrual 1 1    
Other 0 0    
Changes related to unrealized appreciation (depreciation) of investments 0 0    
Net liability for future policy benefits, end of period 55 55    
Less: Reinsurance recoverable: (55) 0    
Net liability for future policy benefits after reinsurance recoverable $ 0 $ 55    
Weighted average liability duration of the liability for future policy benefits (in years) 9 years 1 month 6 days 9 years 4 months 24 days