Reinsurance - Summary of Quota Reinsurance Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Effects of Reinsurance [Line Items]
Ceded losses incurred	$ 38,983	$ 3,431	$ 44,755	$ 5,105
Reinsurance recoverable on loss reserves	63,444	18,402	63,444	18,402	$ 21,641	$ 33,328
Quota Share Reinsurance Agreements, Excluding Captive Agreements
Effects of Reinsurance [Line Items]
Ceded premiums written and earned, net of profit commission	61,357	36,525	88,203	64,689
Ceded losses incurred	38,982	3,440	44,786	5,116
Ceding commissions	12,025	13,356	23,390	26,765
Profit commission	(1,231)	37,021	28,748	75,902
Reinsurance recoverable on loss reserves	$ 63,400		$ 63,400		$ 21,600
Quota Share Reinsurance Agreement, 2015
Effects of Reinsurance [Line Items]
Contingent termination fee		$ 6,800		$ 6,800

Ceded Premiums Written and Earned, Net of Profit Commission

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Reinsurance Ceding Commission Earned

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Reinsurance, Profit Commission

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Reinsurance, Quota Share Reinsurance Agreement, Terms, Contingent Termination Fee

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Amount of reduction of provision for policy benefits and costs incurred for policies ceded.

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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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