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Reinsurance - Schedule of ILN Transactions and XOL Transactions (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Oct. 26, 2021 | Apr. 27, 2021
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Reinsurance Policy, Type [Axis]: 2021-1 ILN |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Percentage of population with production prior to period start date (in percent) | 1.00% |  |
Reinsurance Policy, Type [Axis]: 2021-1 ILN Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage |  |  | $ 367,238
Current Reinsurance Coverage | $ 101,337 |  |
Initial First Layer Retained Loss |  |  | $ 163,708
Current First Layer Retained Loss | $ 162,246 |  |
Reinsurance Policy, Type [Axis]: 2021-2 ILN |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Percentage of population with production prior to period start date (in percent) | 2.00% |  |
Reinsurance Policy, Type [Axis]: 2021-2 ILN Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage |  | $ 363,596 |
Current Reinsurance Coverage | $ 188,327 |  |
Initial First Layer Retained Loss |  | $ 146,229 |
Current First Layer Retained Loss | 144,446 |  |
Reinsurance Policy, Type [Axis]: 2022-1 XOL Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage | 289,741 |  |
Current Reinsurance Coverage | 156,776 |  |
Initial First Layer Retained Loss | 133,366 |  |
Current First Layer Retained Loss | $ 130,371 |  |
Percentage of population with production prior to period start date (in percent) | 1.00% |  |
Reinsurance Policy, Type [Axis]: 2022-2 XOL Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage | $ 154,306 |  |
Current Reinsurance Coverage | 111,008 |  |
Initial First Layer Retained Loss | 78,906 |  |
Current First Layer Retained Loss | $ 74,989 |  |
Percentage of population with production prior to period start date (in percent) | 1.00% |  |
Reinsurance Policy, Type [Axis]: 2022-3 XOL Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage | $ 96,779 |  |
Current Reinsurance Coverage | 71,976 |  |
Initial First Layer Retained Loss | 106,265 |  |
Current First Layer Retained Loss | 102,730 |  |
Reinsurance Policy, Type [Axis]: 2023-1 XOL Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage | 89,864 |  |
Current Reinsurance Coverage | 66,578 |  |
Initial First Layer Retained Loss | 146,513 |  |
Current First Layer Retained Loss | 143,341 |  |
Reinsurance Policy, Type [Axis]: 2023-2 XOL Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage | 100,777 |  |
Current Reinsurance Coverage | 77,129 |  |
Initial First Layer Retained Loss | 136,875 |  |
Current First Layer Retained Loss | 136,070 |  |
Reinsurance Policy, Type [Axis]: 2024 XOL Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage | 162,500 |  |
Current Reinsurance Coverage | 162,500 |  |
Initial First Layer Retained Loss | 312,172 |  |
Current First Layer Retained Loss | 312,057 |  |
Reinsurance Policy, Type [Axis]: 2025 XOL Transaction |  |  |
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items] |  |  |
Initial Reinsurance Coverage | 206,217 |  |
Current Reinsurance Coverage | 206,217 |  |
Initial First Layer Retained Loss | 233,783 |  |
Current First Layer Retained Loss | $ 233,783 |  |

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