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Reinsurance - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Effects of Reinsurance [Line Items]
Ceded losses and loss adjustment expenses	$ 48.7	$ 34.9	$ 61.8
Minimum [Member]
Effects of Reinsurance [Line Items]
Unsecured reinsurance receivable percentage of shareholders' equity	3.00%

X

- Definition

Unsecured Reinsurance Receivables, Percentage of Shareholders Equity

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Amount of reduction of provision for policy benefits and costs incurred for policies ceded.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=99397103&loc=d3e6811-158387

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