Reinsurance - Summary of Quota Reinsurance Arrangements (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Effects of Reinsurance [Line Items]
Ceded losses incurred	$ 8,898	$ 38,983	$ 17,308	$ 44,755
Quota Share Reinsurance Agreements, Excluding Captive Agreements
Effects of Reinsurance [Line Items]
Ceded premiums written and earned, net of profit commission	33,983	61,357	67,373	88,203
Ceded losses incurred	8,903	38,982	17,308	44,786
Ceding commissions	12,991	12,025	26,058	23,390
Profit commission	$ 30,978	$ (1,231)	$ 62,922	$ 28,748