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Reinsurance - Schedule of Disaggregation of Reinsurance Recoverable by Financial Strength Rating and Aging Analysis (Details) - USD ($) $ in Thousands | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | --- | --- | --- | --- | ---
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | $ 687,288 |  | $ 658,525 |  |  |
Less: allowance for credit losses | (1,700) | $ (1,700) | (1,700) | $ (1,800) | $ (2,300) | $ (1,600)
Total reinsurance recoverable, net | 685,588 |  | 656,825 |  |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 684,686 |  | 654,071 |  |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 2,602 |  | 4,454 |  |  |
Federal and state pools |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 83,241 |  | 80,506 |  |  |
Federal and state pools | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 83,241 |  | 80,506 |  |  |
Federal and state pools | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 0 |  | 0 |  |  |
Other than federal and state pools |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 3,948 |  | 4,565 |  |  |
Other than federal and state pools | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 3,785 |  | 4,488 |  |  |
Other than federal and state pools | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 163 |  | 77 |  |  |
Total non-rated reinsurers |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 87,189 |  | 85,071 |  |  |
Total non-rated reinsurers | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 87,026 |  | 84,994 |  |  |
Total non-rated reinsurers | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 163 |  | 77 |  |  |
A++ |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 84,615 |  | 82,487 |  |  |
A++ | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 83,944 |  | 82,466 |  |  |
A++ | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 671 |  | 21 |  |  |
A+ |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 392,660 |  | 374,019 |  |  |
A+ | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 392,094 |  | 371,132 |  |  |
A+ | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 566 |  | 2,887 |  |  |
A |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 117,744 |  | 113,263 |  |  |
A | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 116,631 |  | 111,883 |  |  |
A | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 1,113 |  | 1,380 |  |  |
A- |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 5,080 |  | 3,685 |  |  |
A- | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 4,991 |  | 3,596 |  |  |
A- | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 89 |  | 89 |  |  |
Total rated reinsurers |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 600,099 |  | 573,454 |  |  |
Total rated reinsurers | Current |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | 597,660 |  | 569,077 |  |  |
Total rated reinsurers | Past Due |  |  |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Total reinsurance recoverable, gross | $ 2,439 |  | $ 4,377 |  |  |

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