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Reinsurance Recoverable Credit Ratings (Details) - USD ($) $ in Thousands | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022 | Dec. 31, 2021
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance recoverable, gross | $ 669,342 | $ 784,410 |  |
Reinsurance Recoverable, Allowance for Credit Loss | (2,300) | (1,600) | $ (1,600) | $ (1,600)
Reinsurance recoverable, net of allowance for credit losses | $ 667,042 | 782,810 |  |
National Flood Insurance Program [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Percentage of unpaid NFIP Claims ceded to federal government | 100.00% |  |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | $ 6,730 | 5,011 |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 662,612 | 779,399 |  |
Total federal and state pools [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 104,500 | 180,794 |  |
Change in Reinsurance Recoverable, Gross | (76,300) |  |  |
Total federal and state pools [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 0 | 0 |  |
Total federal and state pools [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 104,500 | 180,794 |  |
Other than Federal And State Pools [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 7,302 | 14,093 |  |
Other than Federal And State Pools [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 497 | 415 |  |
Other than Federal And State Pools [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 6,805 | 13,678 |  |
Non Rated Reinsurer [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 111,802 | 194,887 |  |
Non Rated Reinsurer [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 497 | 415 |  |
Non Rated Reinsurer [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 111,305 | 194,472 |  |
AM Best, A++ Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 81,143 | 46,283 |  |
AM Best, A++ Rating [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 356 | 1 |  |
AM Best, A++ Rating [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 80,787 | 46,282 |  |
AM Best, A+ Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 350,723 | 428,586 |  |
AM Best, A+ Rating [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 3,825 | 3,191 |  |
AM Best, A+ Rating [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 346,898 | 425,395 |  |
AM Best, A Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 121,899 | 107,417 |  |
AM Best, A Rating [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 1,963 | 1,315 |  |
AM Best, A Rating [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 119,936 | 106,102 |  |
AM Best, A- Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 3,775 | 7,237 |  |
AM Best, A- Rating [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 89 | 89 |  |
AM Best, A- Rating [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 3,686 | 7,148 |  |
AM Best Rated Reinsurer [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 557,540 | 589,523 |  |
AM Best Rated Reinsurer [Member] | Financial Asset, Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 6,233 | 4,596 |  |
AM Best Rated Reinsurer [Member] | Financial Asset, Not Past Due |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | $ 551,307 | $ 584,927 |  |

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