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Reinsurance - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2024 | Dec. 31, 2024 | Jun. 30, 2024 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
Ceded Losses and LAE Incurred |  |  |  |  | $ 158,141 | $ 77,203 | $ 666,964
Ceded Premiums Earned |  |  |  |  | 364,618 | 342,623 | $ 251,259
Reinsurance Contract [Axis]: XOL Commutation |  |  |  |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
Ceded Premiums Earned | $ (6,300) |  | $ (15,700) |  |  | $ 6,300 |
Catastrophe Excess of Loss |  |  |  |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
First Event Retention Level |  | $ 20,500 |  |  | 20,500 |  |
Subsequent Event Retention Level |  | 13,000 |  |  | 13,000 |  |
Interboro Insurance | Catastrophe Excess of Loss |  |  |  |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
Reinsurance, Excess Retention, Amount Reinsured, Per Policy |  | 82,500 |  |  |  |  |
Event Retention Level |  | 2,500 |  |  | 2,500 |  |
American Coastal Insurance Company | Catastrophe Excess of Loss |  |  |  |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
Reinsurance, Excess Retention, Amount Reinsured, Per Policy |  | 1,610,000 |  |  |  |  |
Event Retention Level |  | 10,000 |  |  | 10,000 |  |
Reinsurance Retention Policy, Excess Retention, Amount Reinsured |  |  |  |  | 1,260,000 |  |
American Coastal Insurance Company | All Other Perilds Catastrophe Excess of Loss |  |  |  |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
Reinsurance, Excess Retention, Amount Reinsured, Per Policy |  |  |  |  | 172,000 |  |
UPC Re | Catastrophe Excess of Loss |  |  |  |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
First Event Retention Level |  | 10,500 |  |  | 10,500 |  |
Subsequent Event Retention Level |  | $ 3,000 |  |  | $ 3,000 |  |
Subsequent Event | Interboro Insurance | Catastrophe Excess of Loss |  |  |  |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
Event Retention Level |  |  |  | $ 9,800 |  |  |
Subsequent Event | American Coastal Insurance Company | All Other Perilds Catastrophe Excess of Loss |  |  |  |  |  |  |
SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] |  |  |  |  |  |  |
Reinsurance, Excess Retention, Amount Reinsured, Per Policy |  |  |  | 176,400 |  |  |
Reinsurance Retention Policy, Excess Retention, Amount Reinsured |  |  |  | $ 90,000 |  |  |

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