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Reinsurance - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2021 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Reinsurance recoverable on paid losses | $ 36,275 |  |  | $ 36,275 | $ 669 |  |
Reinsurance recoverable on loss reserves | $ 66,905 |  |  | 66,905 | 95,042 | $ 21,641 | $ 33,328
Ceded premiums earned |  |  |  | $ 163,031 | 188,729 | 129,337 |
Quota Share Reinsurance Agreements |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Ceding commission, percentage |  |  |  | 20.00% |  |  |
Annual loss ratio cap | 300.00% |  |  | 300.00% |  |  |
Lifetime loss ratio cap | 200.00% |  |  | 200.00% |  |  |
Threshold for private mortgage insurer eligibility requirements for termination election |  |  |  | 90.00% |  |  |
Contingent termination fee |  |  |  | $ 0 |  |  |
Reinsurance recoverable on loss reserves | $ 66,900 |  |  | $ 66,900 | 95,000 |  |
Credit Union QSR |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Quota Share % |  |  |  | 65.00% |  |  |
Annual loss ratio |  |  |  | 50.00% |  |  |
Threshold for private mortgage insurer eligibility requirements for termination election |  |  |  | 80.00% |  |  |
Excess of Loss Reinsurance Agreements, Home Re Entities |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Ceded premiums earned |  |  |  | $ 44,500 | $ 20,800 | $ 17,600 |
Excess of Loss Reinsurance Agreements, Home Re Entities | Minimum |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Amortization period excess of loss reinsurance coverage |  |  |  | 10 years |  |  |
Excess of Loss Reinsurance Agreements, Home Re Entities | Maximum |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Amortization period excess of loss reinsurance coverage |  |  |  | 12 years 6 months |  |  |
Quota Share Reinsurance Agreement, 2023 | Forecast |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Quota Share % |  | 15.00% | 15.00% |  |  |  |
Annual loss ratio |  |  | 62.00% |  |  |  |
Quota Share Reinsurance Agreements, 2017 & 2018 |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Contingent termination fee | 5,000 |  |  |  |  |  |
Reinsurance recoverable on paid losses | $ 36,000 |  |  | $ 36,000 |  |  |
Home Re special purpose insurers |  |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |  |
Percent of total trust assets invested in cash or direct U.S. federal government obligations |  |  |  | 99.50% |  |  |

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