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Reinsurance - Narrative (Details) - USD ($) $ in Thousands | 6 Months Ended |  |  |
--- | --- | --- | --- | ---
Jun. 30, 2023 | Dec. 31, 2022 | Jun. 30, 2022 | Dec. 31, 2021
Effects of Reinsurance [Line Items] |  |  |  |
Reinsurance recoverable on loss reserves | $ 34,475 | $ 28,240 | $ 53,958 | $ 66,905
Quota Share Reinsurance Transactions |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Ceding commission, percentage (as a percent) | 20.00% |  |  |
Reinsurance, quote share reinsurance agreement, annual loss ratio cap (as a percent) | 300.00% |  |  |
Reinsurance, quota reinsurance agreement, lifetime loss ratio cap (as a percent) | 200.00% |  |  |
Threshold for private mortgage insurer eligibility requirements for termination election (less than) (as a percent) | 90.00% |  |  |
Reinsurance recoverable on loss reserves | $ 34,500 | $ 28,200 |  |
Credit Union QSR Transaction |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Threshold for private mortgage insurer eligibility requirements for termination election (less than) (as a percent) | 80.00% |  |  |
Excess of Loss Reinsurance Transactions, Home Re Transactions |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Percent of reinsurance coverage threshold (as a percent) | 10.00% |  |  |
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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