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Significant Transactions - WM Outrigger Re (Details) - USD ($) $ in Millions |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Dec. 20, 2022 | Jan. 31, 2026 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2025 | Dec. 31, 2024
Outrigger Re |  |  |  |  |  |  |
Other Significant Transactions [Line Items] |  |  |  |  |  |  |
Ceded unearned premiums |  |  | $ 230.0 | $ 250.0 |  | $ 70.0 | $ 230.0
Rollover amount |  |  | 130.0 | $ 130.0 |  |  |
Commitment amount |  |  | 150.0 |  |  |  |
Net distributions |  |  |  |  |  | 9.5 | 122.7
Short-term investments, at fair value |  |  | $ 203.7 |  |  | $ 245.7 | $ 203.7
Outrigger Re | Subsequent Event |  |  |  |  |  |  |
Other Significant Transactions [Line Items] |  |  |  |  |  |  |
Net distributions |  | $ 127.7 |  |  |  |  |
Outrigger Re |  |  |  |  |  |  |
Other Significant Transactions [Line Items] |  |  |  |  |  |  |
Business combination, consideration transferred |  |  |  |  | $ 205.0 |  |
Redeemable Preferred Stock | Outrigger Re Ltd |  |  |  |  |  |  |
Other Significant Transactions [Line Items] |  |  |  |  |  |  |
Issuances of common shares | $ 250.0 |  |  |  |  |  |

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