Liability for Unpaid Losses and Loss Adjustment Expenses - Change in Liability for Unpaid Losses and LAE (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Balance at beginning of period	$ 147,659	$ 288,296	$ 267,760	$ 472,829
Less: Reinsurance recoverable	(26,107)	(197,117)	(123,221)	(393,365)
Net balance at beginning of period	121,552	91,179	144,539	79,464
Incurred (recovered) related to current year	208,392	129,353	489,966	355,258
Incurred (recovered) related to prior years	30,085	3,218	34,904	3,703
Total incurred	238,477	132,571	524,870	358,961
Paid related to Current year	172,977	137,313	355,479	260,955
Paid related to Prior years	43,661	30,408	170,539	121,441
Total paid	216,638	167,721	526,018	382,396
Net balance at end of period	143,391	56,029	143,391	56,029
Plus: Reinsurance recoverable	(59,329)	(110,313)	(59,329)	(110,313)
Balance at end of period	$ 202,720	$ 166,342	$ 202,720	$ 166,342

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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