Liability for Unpaid Losses and Loss Adjustment Expenses - Change in Liability for Unpaid 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
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Balance at beginning of period	$ 244,482	$ 315,780	$ 346,216	$ 322,465
Less: Reinsurance recoverable	(65,403)	(118,671)	(115,860)	(119,522)
Net balance at beginning of period	179,079	197,109	230,356	202,943
Incurred related to current year	196,594	159,490	381,045	304,690
Incurred related to prior years	3,710	7,731	4,365	6,494
Total incurred	200,304	167,221	385,410	311,184
Paid related to current year	164,888	151,348	236,615	205,829
Paid related to prior years	47,118	47,481	211,774	142,797
Total paid	212,006	198,829	448,389	348,626
Net balance at end of period	167,377	165,501	167,377	165,501
Plus: Reinsurance recoverable	18,972	113,157	18,972	113,157
Balance at end of period	$ 186,349	$ 278,658	$ 186,349	$ 278,658

The amount needed to reflect the estimated ultimate cost of settling claims relating to insured events that have occurred on or before 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, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and 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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