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Reinsurance Recoverable Credit Ratings (Details) - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019
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Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator, Date Updated | Mar. 31, 2021 |  |  |
Reinsurance recoverable | $ 582,696 | $ 589,269 |  |
Reinsurance Recoverable, Allowance for Credit Loss | (1,840) | (1,777) | $ (1,502) | $ (4,400)
Reinsurance recoverable, net of allowance for credit losses | 580,856 | 587,492 |  |
AM Best, A++ Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 38,047 | 37,566 |  |
Reinsurance Recoverable, Current | 37,939 | 37,464 |  |
Reinsurance Recoverable, Past Due | 108 | 102 |  |
AM Best, A+ Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 356,418 | 357,298 |  |
Reinsurance Recoverable, Current | 352,386 | 354,846 |  |
Reinsurance Recoverable, Past Due | 4,032 | 2,452 |  |
AM Best, A Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 105,455 | 106,067 |  |
Reinsurance Recoverable, Current | 105,068 | 105,652 |  |
Reinsurance Recoverable, Past Due | 387 | 415 |  |
AM Best, A- Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 2,177 | 2,139 |  |
Reinsurance Recoverable, Current | 2,177 | 2,139 |  |
Reinsurance Recoverable, Past Due | 0 | 0 |  |
AM Best, B++ Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 381 | 380 |  |
Reinsurance Recoverable, Current | 117 | 56 |  |
Reinsurance Recoverable, Past Due | 264 | 324 |  |
AM Best, B+ Rating [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 0 | 0 |  |
Reinsurance Recoverable, Current | 0 | 0 |  |
Reinsurance Recoverable, Past Due | 0 | 0 |  |
AM Best Rated Reinsurer [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 502,478 | 503,450 |  |
Reinsurance Recoverable, Current | 497,687 | 500,157 |  |
Reinsurance Recoverable, Past Due | 4,791 | 3,293 |  |
Total federal and state pools [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 76,179 | 82,575 |  |
Reinsurance Recoverable, Current | 76,179 | 82,575 |  |
Reinsurance Recoverable, Past Due | 0 | 0 |  |
Other than Federal And State Pools [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 4,039 | 3,244 |  |
Reinsurance Recoverable, Current | 3,179 | 2,676 |  |
Reinsurance Recoverable, Past Due | 860 | 568 |  |
Total Non Rated Reinsurer [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverables, Gross | 80,218 | 85,819 |  |
Reinsurance Recoverable, Current | 79,358 | 85,251 |  |
Reinsurance Recoverable, Past Due | 860 | 568 |  |
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] |  |  |  |
Reinsurance Recoverable, Credit Quality Indicator [Line Items] |  |  |  |
Reinsurance Recoverable, Current | 577,045 | 585,408 |  |
Reinsurance Recoverable, Past Due | $ 5,651 | $ 3,861 |  |

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- Definition Date of last update of credit quality indicator for reinsurance recoverable, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919230-210447 + Details
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- Definition Amount of reinsurance recoverable, not past due. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919253-210447 + 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/2003/role/disclosureRef -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=120400017&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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