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Concentration of Operations - Net Premiums Earned for the Top Ten States (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 270,639 | $ 267,125 | $ 271,698
Premium earned percentage | 100.00% | 100.00% | 100.00%
Florida [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 38,976 | $ 33,838 | $ 31,955
Premium earned percentage | 14.40% | 12.70% | 11.80%
Georgia [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 28,267 | $ 30,504 | $ 30,831
Premium earned percentage | 10.40% | 11.40% | 11.30%
Pennsylvania [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 19,564 | $ 19,963 | $ 21,017
Premium earned percentage | 7.20% | 7.50% | 7.70%
Louisiana [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 16,998 | $ 21,150 | $ 21,804
Premium earned percentage | 6.30% | 7.90% | 8.00%
Illinois [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 16,294 | $ 13,072 | $ 12,209
Premium earned percentage | 6.00% | 4.90% | 4.50%
North Carolina [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 15,863 | $ 16,432 | $ 17,883
Premium earned percentage | 5.90% | 6.20% | 6.60%
Texas [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 10,886 | $ 6,151 | $ 6,307
Premium earned percentage | 4.00% | 2.30% | 2.30%
Wisconsin [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 10,769 | $ 11,724 | $ 12,007
Premium earned percentage | 4.00% | 4.40% | 4.40%
Virginia [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 10,151 | $ 10,400 | $ 11,537
Premium earned percentage | 3.80% | 3.80% | 4.30%
South Carolina [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 8,603 | $ 9,050 | $ 9,808
Premium earned percentage | 3.20% | 3.40% | 3.60%
All Others [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 94,268 | $ 94,841 | $ 96,340
Premium earned percentage | 34.80% | 35.50% | 35.50%

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