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Reinsurance - Schedule of Unsecured Reinsurance Recoverables from Reinsurers (Detail) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables |  | $ 129,963 | $ 125,677
Allowance for credit losses |  | (360) | $ (372)
Funds withheld and letters of credit related to the above recoverables |  | (81,520) |
Total unsecured amounts recoverable from reinsurers |  | 48,443 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk |  |  |
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables |  | 129,963 |
Total amounts recoverable from reinsurers |  | 130,323 |
Allowance for credit losses |  | (360) |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Hannover Reinsurance (Ireland) Limited [Member] | A.M. Best Rating, A+ [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables | [1] | 65,045 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Arch Reinsurance Company |  |  |
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables | [1] | 19,694 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Allianz Risk Transfer AG (Bermuda) [Member] | A.M. Best Rating, A+ [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables |  | 9,084 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Minnesota Workers' Compensation Reinsurance Association [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables | [1] | 8,950 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Munich Reinsurance America, Inc [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables | [1] | 5,542 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Odyssey America Reinsurance Corporation [Member] | A.M. Best Rating, A [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables |  | 4,961 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Other Reinsurers [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Total reinsurance recoverables |  | $ 17,047 |
[1] | Current participant in our 2024 reinsurance program.

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- Definition Letters of credit from the reinsurer and Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations there under. + 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 825 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Publisher FASB -URI https://asc.fasb.org//1943274/2147479383/944-825-50-1B + Details
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- Definition Amount, after valuation allowance, recoverable under reinsurance contracts including premium paid under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479838/944-20-50-5 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 310 -Name Accounting Standards Codification -Section 45 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479616/944-310-45-5 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 + Details
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- Definition Amount before 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, premium paid, policy benefits and policy reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479838/944-20-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 310 -Name Accounting Standards Codification -Section 45 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479616/944-310-45-5 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-14 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 7A -SubTopic 10 -Topic 310 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-7A + Details
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