Losses and Loss Adjustment Expenses - Losses and LAE (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Net balance, beginning of period*	$ 179,837	$ 144,630	$ 172,410	$ 141,065
Incurred, net of reinsurance, related to:
Current period	78,448	51,310	148,524	93,230
Prior period	8,382	4,607	11,010	8,438
Total incurred, net of reinsurance	86,830	55,917	159,534	101,668
Paid, net of reinsurance, related to:
Current period	(37,627)	(20,006)	(56,423)	(27,602)
Prior period	(32,626)	(25,640)	(79,107)	(60,230)
Total paid, net of reinsurance	(70,253)	(45,646)	(135,530)	(87,832)
Net balance, end of period	196,414	154,901	196,414	154,901
Add: reinsurance recoverable before allowance for credit losses	42,410	48,884	42,410	48,884
Gross balance, end of period	$ 238,824	$ 203,785	$ 238,824	$ 203,785	$ 237,165

The amount needed to reflect the estimated ultimate cost of settling claims relating to casualty insurance insured events that have occurred on or before a particular date (ordinarily, the balance sheet date) and the amount needed to provide for the estimated ultimate cost required to investigate and settle claims relating to insured events that have occurred on or before a particular date (ordinarily, the balance sheet date), whether or not reported to the insurer at that date.

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Amount, after effects of reinsurance, of payments to settle claims incurred in the current period and related claims settlement costs.

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Amount, after effects of reinsurance, of payments to settle claims incurred in prior periods and related claims settlement costs.

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Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred and costs incurred in the claim settlement process.

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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount, after effects of reinsurance, of payments to settle insured claims and pay costs incurred in the claims settlement process.

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Amount before valuation allowance of reinsurance recoverables for losses reported to the ceding insurer but not yet paid, and for amounts expected based upon statistical projections and other measures of incurred losses and loss settlement expenses which have not yet been reported to the ceding insurer.

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Amount, after effects of reinsurance, of expense for claims incurred in the current reporting period and related claims settlement costs.

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Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

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