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, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Balance at beginning of period	$ 195,978	$ 366,356	$ 267,760	$ 472,829
Less: Reinsurance recoverable	(66,158)	(269,071)	(123,221)	(393,365)
Net balance at beginning of period	129,820	97,285	144,539	79,464
Incurred (recovered) related to current year	150,867	112,626	281,574	225,905
Incurred (recovered) related to prior years	478	670	4,819	485
Total incurred	151,345	113,296	286,393	226,390
Paid related to Current year	120,724	89,093	182,502	123,642
Paid related to Prior years	38,889	30,309	126,878	91,033
Total paid	159,613	119,402	309,380	214,675
Net balance at end of period	121,552	91,179	121,552	91,179
Plus: Reinsurance recoverable	(26,107)	(197,117)	(26,107)	(197,117)
Balance at end of period	$ 147,659	$ 288,296	$ 147,659	$ 288,296

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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