v3.25.2
Separate Account Balances - Retirement and Income Solutions (Details) - USD ($)
$ in Millions
6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Changes in separate account liabilities    
Balance at beginning of period $ 173,327.1  
Balance at end of period 180,728.0 $ 173,327.1
Retirement and Income Solutions    
Changes in separate account liabilities    
Balance at beginning of period 133,438.0  
Balance at end of period 136,140.3 133,438.0
Retirement and Income Solutions | Group retirement contracts    
Changes in separate account liabilities    
Balance at beginning of period 125,103.1 117,518.5
Premiums and deposits 7,242.8 16,573.1
Policy charges (163.4) (365.6)
Surrenders, withdrawals and benefit payments (8,592.2) (19,191.4)
Investment performance 6,309.7 14,632.1
Net transfers (to) from general account (1,620.4) (4,148.3)
Other 153.1 84.7
Balance at end of period 128,432.7 125,103.1
Cash surrender value 127,113.6 123,965.4
Retirement and Income Solutions | Individual variable annuities    
Changes in separate account liabilities    
Balance at beginning of period 8,334.9 9,131.9
Premiums and deposits 85.6 344.5
Policy charges (85.4) (197.6)
Surrenders, withdrawals and benefit payments (947.2) (1,977.7)
Investment performance 337.3 1,079.0
Net transfers (to) from general account (17.6) (2.1)
Other   (43.1)
Balance at end of period 7,707.6 8,334.9
Cash surrender value $ 7,599.4 $ 8,219.1