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Reinsurance - Disaggregation of Reinsurance Recoverable by Financial Strength Rating and Aging Analysis (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023 | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | --- | --- | ---
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | $ 653,085 | $ 658,525 |  |
Less: allowance for credit losses | (1,700) | (1,700) | $ (2,300) | $ (1,600)
Total reinsurance recoverable, net | 651,385 | 656,825 |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 653,085 |  |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 650,685 | 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 | 2,400 | 4,454 |  |
Federal and state pools |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 77,799 | 80,506 |  |
Federal and state pools | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 77,799 | 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 | 4,639 | 4,565 |  |
Other than federal and state pools | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 4,135 | 4,488 |  |
Other than federal and state pools | Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 504 | 77 |  |
Total non-rated reinsurers |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 82,438 | 85,071 |  |
Total non-rated reinsurers | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 81,934 | 84,994 |  |
Total non-rated reinsurers | Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 504 | 77 |  |
A++ |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 83,425 | 82,487 |  |
A++ | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 83,372 | 82,466 |  |
A++ | Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 53 | 21 |  |
A+ |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 367,600 | 374,019 |  |
A+ | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 366,428 | 371,132 |  |
A+ | Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 1,172 | 2,887 |  |
A |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 115,668 | 113,263 |  |
A | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 115,086 | 111,883 |  |
A | Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 582 | 1,380 |  |
A- |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 3,954 | 3,685 |  |
A- | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 3,865 | 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 | 570,647 | 573,454 |  |
Total rated reinsurers | Current |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | 568,751 | 569,077 |  |
Total rated reinsurers | Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Total reinsurance recoverable, gross | $ 1,896 | $ 4,377 |  |

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