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Reinsurance - Schedule of Unsecured Reinsurance Recoverables from Reinsurers (Detail) - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
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Ceded Credit Risk [Line Items] |  |  |
Amounts recoverable from reinsurers |  | $ 112,006 | $ 90,133
Funds withheld and letters of credit related to the above recoverables |  | (69,932) |
Total unsecured amounts recoverable from reinsurers |  | 42,074 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk |  |  |
Ceded Credit Risk [Line Items] |  |  |
Amounts recoverable from reinsurers |  | 112,006 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Hannover Reinsurance (Ireland) Limited [Member] | A.M. Best Rating, A+ [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Amounts recoverable from reinsurers | [1] | 53,609 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Allianz Risk Transfer AG (Bermuda) [Member] | A.M. Best Rating, A+ [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Amounts recoverable from reinsurers | [1] | 13,084 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Odyssey America Reinsurance Corporation [Member] | A.M. Best Rating, A [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Amounts recoverable from reinsurers |  | 11,754 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Minnesota Workers’ Compensation Reinsurance Association [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Amounts recoverable from reinsurers | [1] | 8,823 |
Reinsurance Recoverable [Member] | Reinsurer Concentration Risk | Other Reinsurers [Member] |  |  |
Ceded Credit Risk [Line Items] |  |  |
Amounts recoverable from reinsurers |  | $ 24,736 |
[1] | Current participant in our 2019 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 Unsecured amounts recoverables from reinsurance net. + 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, 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),6) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 20 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=99397103&loc=d3e6824-158387 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=99404803&loc=d3e21409-158489 + Details
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