Commitments and Contingencies - Schedule of Company's Restricted Assets (Details) - USD ($) $ in Millions |
12 Months Ended | |||
|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
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| Commitments and Contingencies Disclosure [Abstract] | ||||
| Affiliated transactions | $ 227.3 | $ 433.4 | ||
| Third party | 2,470.3 | 2,713.5 | ||
| Letters of credit / guarantees (1) | 101.8 | 153.2 | ||
| Total restricted assets (excluding illiquid assets) | 2,799.4 | 3,300.1 | ||
| Other Investments | [1] | 279.6 | 267.2 | |
| Total restricted assets and illiquid assets | $ 3,079.0 | $ 3,567.3 | ||
| Total as percent of invested assets | 37.10% | 46.40% | ||
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