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Reinsurance - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Effects of Reinsurance [Line Items] |  |  |  |  |
Reinsurance recoverable on paid losses |  | $ 18,081 | $ 36,275 |  |
Reinsurance recoverable on loss reserves |  | $ 28,240 | 66,905 | $ 95,042 | $ 21,641
Quota Share Reinsurance Transactions |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |
Ceding commission, percentage |  | 20.00% |  |  |
Annual loss ratio cap, percentage |  | 300.00% |  |  |
Lifetime loss ratio cap, percentage |  | 200.00% |  |  |
Threshold for private mortgage insurer eligibility requirements for termination election |  | 90.00% |  |  |
Reinsurance recoverable on loss reserves |  | $ 28,200 | 66,900 |  |
Credit Union QSR Transaction |  |  |  |  |
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% |  |  |
Quota Share Reinsurance Transaction, 2023 | Forecast |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |
Quota Share % | 10.00% |  |  |  |
Annual loss ratio | 58.50% |  |  |  |
2019 QSR Transaction |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |
Quota Share % |  | 30.00% |  |  |
Annual loss ratio |  | 62.00% |  |  |
Contingent termination fee |  | $ 2,200 |  |  |
Quota Share Reinsurance Transactions, 2015 & 2019 |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |
Reinsurance recoverable on paid losses |  | $ 17,700 |  |  |
Quota Share Reinsurance Transactions, 2017 & 2018 |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |
Contingent termination fee |  |  | 5,000 |  |
Reinsurance recoverable on paid losses |  |  | $ 36,000 |  |
Aggregate Excess of Loss Reinsurance Transactions, Home Re Entities | Minimum |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |
Amortization period excess of loss reinsurance coverage |  | 10 years |  |  |
Aggregate Excess of Loss Reinsurance Transactions, Home Re Entities | Maximum |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |
Amortization period excess of loss reinsurance coverage |  | 12 years 6 months |  |  |
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 (as a percent) |  | 99.50% |  |  |

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