Reinsurance - Reinsurance Arrangements (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Reinsurance Disclosures [Abstract]
Direct premiums written	$ 578,267	$ 547,126	$ 1,024,446	$ 957,228
Ceded premiums written	(632,813)	(561,480)	(633,104)	(576,256)
Net premiums written	(54,546)	(14,354)	391,342	380,972
Direct premiums earned	490,649	463,324	972,721	918,692
Ceded premiums earned	(145,691)	(160,050)	(293,738)	(333,194)
Premiums earned, net	344,958	303,274	678,983	585,498
Direct losses and loss adjustment expenses	253,613	253,079	493,932	461,301
Ceded losses and loss adjustment expenses	(10,041)	(29,352)	(10,173)	(31,420)
Net Losses and Loss Adjustment Expenses	$ 243,572	$ 223,727	$ 483,759	$ 429,881

Amount of earned premiums ceded to other entities.

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