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Reinsurance Recoverable, Credit Quality Indicator (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverable, Credit Quality Indicator, Date Updated	Dec. 31, 2020
Reinsurance Recoverables, Gross	$ 589,269	$ 577,635
Reinsurance Recoverable, Allowance for Credit Loss	(1,777)	(4,400)
Reinsurance Recoverables, net of allowance for credit losses	587,492	$ 573,235
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverable, Current	585,408
Reinsurance Recoverable, Past Due	3,861
Total federal and state pools [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	82,575
Reinsurance Recoverable, Current	82,575
Reinsurance Recoverable, Past Due	0
Other Federal And State Pools [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	3,244
Reinsurance Recoverable, Current	2,676
Reinsurance Recoverable, Past Due	568
Total Non Rated Reinsurer [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	85,819
Reinsurance Recoverable, Current	85,251
Reinsurance Recoverable, Past Due	568
AM Best, A++ Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	37,566
Reinsurance Recoverable, Current	37,464
Reinsurance Recoverable, Past Due	102
AM Best, A+ Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	357,298
Reinsurance Recoverable, Current	354,846
Reinsurance Recoverable, Past Due	2,452
AM Best, A Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	106,067
Reinsurance Recoverable, Current	105,652
Reinsurance Recoverable, Past Due	415
AM Best, A- Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	2,139
Reinsurance Recoverable, Current	2,139
Reinsurance Recoverable, Past Due	0
AM Best, B++ Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	380
Reinsurance Recoverable, Current	56
Reinsurance Recoverable, Past Due	324
AM Best, B+ Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	0
Reinsurance Recoverable, Current	0
Reinsurance Recoverable, Past Due	0
AM Best Rated Reinsurer [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	503,450
Reinsurance Recoverable, Current	500,157
Reinsurance Recoverable, Past Due	$ 3,293

X

- 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)
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- Definition

Amount of reinsurance recoverable, not past due.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
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Amount of reinsurance recoverable past due.

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-Topic 326
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-Section 50
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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))
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Amount of allowance for credit loss on reinsurance recoverable.

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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

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Amount before valuation allowance of reinsurance recoverables for losses reported to the ceding insurer but not yet paid, and for amounts expected based upon statistical projections and other measures of incurred losses and loss settlement expenses which have not yet been reported to the ceding insurer.

+ References

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