Deferred Acquisition Costs and Other Actuarial Balances - Unearned Revenue Liability Balances and Changes (Details) - USD ($) $ in Millions |
6 Months Ended | 12 Months Ended |
|---|---|---|
Jun. 30, 2025 |
Dec. 31, 2024 |
|
| Other Actuarial Balances | ||
| Beginning balance, Unearned Revenue Liability | $ 515.4 | |
| Ending balance, Unearned Revenue Liability | 527.5 | $ 515.4 |
| Universal life | Benefits and Protection | Life Insurance | ||
| Other Actuarial Balances | ||
| Beginning balance, Unearned Revenue Liability | 510.1 | 485.5 |
| Deferrals | 28.9 | 56.1 |
| Revenue recognized | (16.6) | (31.5) |
| Ending balance, Unearned Revenue Liability | 522.4 | 510.1 |
| Reinsurance impact | (218.3) | (220.8) |
| Balance at end of period after reinsurance | $ 304.1 | $ 289.3 |