Reinsurance Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effects of Reinsurance [Line Items]
Reinsurance receivables, net	$ 88,708	$ 83,938
Collateral securing reinsurance receivables	(4,984)	(3,802)
Reinsurance receivables, net of collateral	83,724	80,136
Prepaid reinsurance premiums	12,881	16,716
Allowance for Reinsurance Recoverable
Effects of Reinsurance [Line Items]
Allowance for uncollectible reinsurance receivables	$ 8,992	$ 8,992	$ 8,040	$ 8,040

Collateral Securing Reinsurance Receivables

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- Definition

Reinsurance Receivable Net Of Collateral

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The unexpired portion of premiums ceded on policies in force as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 340
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- Definition

Amount, after valuation allowance, recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, policy benefits and policy reserves. Excludes premiums paid under reinsurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of valuation and qualifying accounts and reserves.

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