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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, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 267,125 | $ 271,698 | $ 275,993
Premium earned percentage | 100.00% | 100.00% | 100.00%
Florida [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 33,838 | $ 31,955 | $ 31,514
Premium earned percentage | 12.70% | 11.80% | 11.40%
Georgia [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 30,504 | $ 30,831 | $ 34,772
Premium earned percentage | 11.40% | 11.30% | 12.60%
Louisiana [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 21,150 | $ 21,804 | $ 20,476
Premium earned percentage | 7.90% | 8.00% | 7.40%
Pennsylvania [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 19,963 | $ 21,017 | $ 19,574
Premium earned percentage | 7.50% | 7.70% | 7.10%
North Carolina [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 16,432 | $ 17,883 | $ 15,964
Premium earned percentage | 6.20% | 6.60% | 5.80%
Illinois [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 13,072 | $ 12,209 | $ 13,680
Premium earned percentage | 4.90% | 4.50% | 5.00%
Wisconsin [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 11,724 | $ 12,007 | $ 13,108
Premium earned percentage | 4.40% | 4.40% | 4.70%
Virginia [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 10,400 | $ 11,537 | $ 12,579
Premium earned percentage | 3.80% | 4.30% | 4.60%
South Carolina [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 9,050 | $ 9,808 | $ 9,186
Premium earned percentage | 3.40% | 3.60% | 3.30%
Minnesota [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 8,845 | $ 9,827 | $ 10,612
Premium earned percentage | 3.30% | 3.60% | 3.80%
All Others [Member] |  |  |
Schedule Of Premiums Earned Net By Segment [Line Items] |  |  |
Net premiums earned | $ 92,147 | $ 92,820 | $ 94,528
Premium earned percentage | 34.50% | 34.20% | 34.30%

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