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Reinsurance - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021 | Dec. 31, 2021 | Dec. 31, 2020
Effects of Reinsurance [Line Items] |  |  |  |  |  |
Reinsurance recoverable on paid losses | $ 310 |  | $ 310 |  | $ 36,275 |
Reinsurance recoverable on loss reserves | 53,958 | $ 111,153 | 53,958 | $ 111,153 | 66,905 | $ 95,042
Ceded premiums | $ 34,270 | 43,988 | 68,429 | 87,625 |  |
Reinsurance Contract [Axis]: Excess of Loss Reinsurance Coverage on New Insurance Written |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |
Excess of loss reinsurance coverage |  |  | $ 175,000 |  |  |
Approximate contractual termination term | 10 years |  | 10 years |  |  |
Optional termination term | 7 years |  | 7 years |  |  |
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% |  |  |
Quota Share Reinsurance Transactions |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |
Ceding commission, percentage (as a percent) |  |  | 20.00% |  |  |
Reinsurance, Quota Share Reinsurance Agreement, Terms, Annual Loss Ratio Cap | 300.00% |  | 300.00% |  |  |
Reinsurance, Quota Share Reinsurance Agreement, Terms, Lifetime Loss Ratio Cap | 200.00% |  | 200.00% |  |  |
Threshold for private mortgage insurer eligibility requirements for termination election (less than) (as a percent) |  |  | 90.00% |  |  |
Reinsurance recoverable on loss reserves | $ 54,000 |  | $ 54,000 |  | 66,900 |
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% |  |  |
QSR Transactions, 2017 & 2018 |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |
Reinsurance recoverable on paid losses |  |  |  |  | $ 36,000 |
Aggregate Excess of Loss Reinsurance Transactions, Home Re |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |
Ceded premiums | $ 18,200 | $ 10,000 | $ 30,000 | $ 20,300 |  |
Aggregate Excess of Loss Reinsurance Transactions, Home Re | Minimum |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |
Amortization period excess of loss reinsurance coverage |  |  | 10 years |  |  |
Aggregate Excess of Loss Reinsurance Transactions, Home Re | Maximum |  |  |  |  |  |
Effects of Reinsurance [Line Items] |  |  |  |  |  |
Amortization period excess of loss reinsurance coverage |  |  | 12 years 6 months |  |  |

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