Reinsurance - Reinsurance Arrangements (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Reinsurance Disclosures [Abstract]
Direct premiums written	$ 446,179	$ 410,102
Ceded premiums written	(291)	(14,776)
Net premiums written	445,888	395,326
Direct premiums earned	482,072	455,368
Ceded premiums earned	(148,047)	(173,144)
Premiums earned, net	334,025	282,224
Direct losses and loss adjustment expenses	240,319	208,222
Ceded losses and loss adjustment expenses	(132)	(2,068)
Net Losses and Loss Adjustment Expenses	$ 240,187	$ 206,154

Amount of earned premiums ceded to other entities.

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