Reinsurance - Schedule of Unsecured Reinsurance Recoverables from Reinsurers (Detail) - USD ($) $ in Thousands		Dec. 31, 2025	Dec. 31, 2024
Ceded Credit Risk [Line Items]
Total reinsurance recoverables		$ 108,098	$ 117,019
Allowance for credit losses		(264)	$ (300)
Funds withheld and letters of credit related to the above recoverables		(63,886)
Total unsecured amounts recoverable from reinsurers		44,212
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk
Ceded Credit Risk [Line Items]
Total reinsurance recoverables		108,098
Total amounts recoverable from reinsurers		108,362
Allowance for credit losses		(264)
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Hannover Reinsurance (Ireland) Limited [Member] | A.M. Best Rating, A+ [Member]
Ceded Credit Risk [Line Items]
Total reinsurance recoverables	[1]	41,924
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Arch Reinsurance Company | A.M. Best Rating, A+ [Member]
Ceded Credit Risk [Line Items]
Total reinsurance recoverables	[1]	27,750
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Munich Reinsurance America, Inc [Member] | A.M. Best Rating, A+ [Member]
Ceded Credit Risk [Line Items]
Total reinsurance recoverables	[1]	10,179
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Minnesota Workers' Compensation Reinsurance Association [Member]
Ceded Credit Risk [Line Items]
Total reinsurance recoverables	[1]	8,758
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Allianz Risk Transfer AG (Bermuda) [Member] | A.M. Best Rating, A+ [Member]
Ceded Credit Risk [Line Items]
Total reinsurance recoverables		3,525
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Odyssey America Reinsurance Corporation [Member] | A.M. Best Rating, A+ [Member]
Ceded Credit Risk [Line Items]
Total reinsurance recoverables		3,411
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Other Reinsurers [Member]
Ceded Credit Risk [Line Items]
Total reinsurance recoverables		$ 12,815

[1] Current participant in our 2026 reinsurance program.