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Disaggregation of Reinsurance Recoverable by Financial Strength Rating and Aging Analysis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance recoverable, gross	$ 687,141		$ 784,410
Reinsurance Recoverable, Allowance for Credit Loss	(1,800)	$ (1,800)	(1,600)	$ (1,600)	$ (1,600)	$ (1,600)
Reinsurance recoverable, net of allowance for credit losses	685,341		782,810
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	7,192		5,011
Reinsurance Recoverable for Paid and Unpaid Claims and Claims Adjustments, Gross [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	679,949		779,399
Total federal and state pools [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	88,793		180,794
Total federal and state pools [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	16		0
Total federal and state pools [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	88,777		180,794
Other than Federal And State Pools [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	6,437		14,093
Other than Federal And State Pools [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	210		415
Other than Federal And State Pools [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	6,227		13,678
Non Rated Reinsurer [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	95,230		194,887
Non Rated Reinsurer [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	226		415
Non Rated Reinsurer [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	95,004		194,472
AM Best, A++ Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	87,315		46,283
AM Best, A++ Rating [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	20		1
AM Best, A++ Rating [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	87,295		46,282
AM Best, A+ Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	381,954		428,586
AM Best, A+ Rating [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	4,876		3,191
AM Best, A+ Rating [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	377,078		425,395
AM Best, A Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	118,884		107,417
AM Best, A Rating [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	1,981		1,315
AM Best, A Rating [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	116,903		106,102
AM Best, A- Rating [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	3,758		7,237
AM Best, A- Rating [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	89		89
AM Best, A- Rating [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	3,669		7,148
AM Best Rated Reinsurer [Member]
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	591,911		589,523
AM Best Rated Reinsurer [Member] | Financial Asset, Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	6,966		4,596
AM Best Rated Reinsurer [Member] | Financial Asset, Not Past Due
Reinsurance Recoverable, Credit Quality Indicator [Line Items]
Reinsurance Recoverables, Gross	$ 584,945		$ 584,927

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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.

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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.

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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.

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