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Reinsurance - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
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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% |  |

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- 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 + Details
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- Details
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