Reinsurance - Schedule of reinsurance (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Dec. 31, 2019
Effects of Reinsurance [Line Items]
Direct Unearned Premium	$ 17,393	$ 16,070
Ceded Unearned Premium	0	(13,668)
Ceded Loss and LAE Reserves	0	(33,941)	$ (33,583)	$ (28,837)
Net Premium Written	63,985	15,107
Net Premium Earned	48,993	14,972
Net Unearned Premium	17,393	2,402
Net Losses and LAE Incurred	62,272	20,933
Net Loss and LAE Reserves	70,798	23,152
Direct
Effects of Reinsurance [Line Items]
Direct Premium Written	83,396	100,611
Direct Premium Earned	82,073	99,712
Direct Unearned Premium	17,393	16,070
Direct Losses and LAE Incurred	76,973	74,943
Direct Loss and LAE Reserves	70,798	57,093
Ceded
Effects of Reinsurance [Line Items]
Ceded Premium Written	(19,411)	(85,504)
Ceded Premium Earned	(33,080)	(84,740)
Ceded Unearned Premium	0	(13,668)
Ceded Losses and LAE Incurred	(14,701)	(54,010)
Ceded Loss and LAE Reserves	$ 0	$ (33,941)

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written.

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Amount, before premiums ceded to other entities and premiums assumed by the entity, of premiums earned.

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Amount, before effect of policies assumed or ceded, of expense related to provision for policy benefits and costs incurred.

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Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written.

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Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

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Carrying amount of premiums written on insurance contracts that have not been earned as of the balance sheet date.

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