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Reinsurance - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2026 | Dec. 31, 2025 | Mar. 31, 2025 | Dec. 31, 2024
Effects of Reinsurance [Line Items] |  |  |  |
Reinsurance recoverable on loss reserves | $ 73,184 | $ 65,055 | $ 51,864 | $ 47,281
Eligible New Insurance Written In 2027 |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Reinsurance, quota share reinsurance agreement, terms, quota share, percent | 40.00% |  |  |
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 | $ 73,200 | $ 65,100 |  |
Credit Union QSR |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |
Threshold for private mortgage insurer eligibility requirements for termination election (less than) (as a percent) | 80.00% |  |  |
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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