Reinsurance - Schedule of Effects of Reinsurance (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Reinsurance Disclosures [Abstract]
Direct premiums written	$ 180,925	$ 147,452
Assumed Premiums Written	31,225	0
Gross Premiums Written	212,150	147,452
Ceded premiums written	(58,754)	(40,987)
Net premiums written	153,396	106,465
Direct premiums earned	166,771	156,928
Assumed Premiums Earned	43,385	0
Gross Premiums Earned	210,156	156,928
Ceded premiums earned	(144,754)	(117,645)
Net premiums earned	$ 65,402	$ 39,283

Premiums Earned Gross

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Amount of written premiums assumed from other entities.

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Amount of earned premiums ceded to other entities.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums written.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written.

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