Separate Account Balances - Separate Account Liabilities (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|---|
| Separate Account Balances | |||
| Separate account liabilities | $ 202,396.0 | $ 193,622.6 | |
| Other balances | |||
| Separate Account Balances | |||
| Separate account liabilities | 330.3 | 325.0 | |
| Retirement and Income Solutions | |||
| Separate Account Balances | |||
| Separate account liabilities | 150,330.8 | 144,039.2 | |
| Retirement and Income Solutions | Group retirement contracts | |||
| Separate Account Balances | |||
| Separate account liabilities | 143,243.9 | 136,674.3 | $ 125,103.1 |
| Retirement and Income Solutions | Individual variable annuities | |||
| Separate Account Balances | |||
| Separate account liabilities | 7,086.9 | 7,364.9 | 8,334.9 |
| Principal Asset Management | International Pension | Pension | Latin America | |||
| Separate Account Balances | |||
| Separate account liabilities | 43,323.8 | 41,450.5 | 32,802.2 |
| Benefits and Protection | Life Insurance | Universal life | |||
| Separate Account Balances | |||
| Separate account liabilities | $ 8,411.1 | $ 7,807.9 | $ 6,806.7 |