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Reinsurance - Schedule of the Effect of Reinsurance on Premiums Written and Earned (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Premiums Written and Earned [Abstract] |  |  |
Gross Written | $ 285,355 | $ 276,110 | $ 278,294
Ceded Written | (16,621) | (10,527) | (10,469)
Net premiums Written | 268,734 | 265,583 | 267,825
Gross Earned | 283,746 | 282,225 | 286,462
Ceded Earned | (16,621) | (10,527) | (10,469)
Net premiums Earned | $ 267,125 | $ 271,698 | $ 275,993

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