Losses and Loss Adjustment Expenses - Losses and LAE (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Liability For Unpaid Claims And Claims Adjustment Expense Net [Abstract]
Net balance, beginning of year*	$ 141,065	$ 98,174	$ 94,826
Incurred, net of reinsurance, related to:
Current year	199,888	158,236	96,955
Prior years	27,637	1,800	10,559
Total incurred, net of reinsurance	227,525	160,036	107,514
Paid, net of reinsurance, related to:
Current year	(95,809)	(71,772)	(48,456)
Prior years	(100,371)	(45,373)	(55,710)
Total paid, net of reinsurance	(196,180)	(117,145)	(104,166)
Net balance, end of year	172,410	141,065	98,174
Add: reinsurance recoverable	64,755	71,104	116,523
Gross balance, end of year	$ 237,165	$ 212,169	$ 214,697

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437

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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.

+ References

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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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