Unpaid Losses and Loss Adjustment Expenses - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Sep. 28, 2017	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2017
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year adjustments			$ 19,432	$ 15,594	$ 10,552
Losses and loss adjustment expenses, net			69,861	56,228	59,744
Unpaid losses and loss adjustment expenses			$ 139,085	111,270	107,246	$ 92,807
Adverse Development Cover Reinsurance Agreement
Liability for Claims and Claims Adjustment Expense [Line Items]
Amount reinsured	$ 17,500
Reinsurance retention policy, co-participation (percentage)	10.00%
Maximum
Liability for Claims and Claims Adjustment Expense [Line Items]
Reinsurance retention policy, co-participation (percentage)			60.00%
Maximum | Adverse Development Cover Reinsurance Agreement
Liability for Claims and Claims Adjustment Expense [Line Items]
Reinsurance retention policy carried reserves threshold	$ 19,500
Unpaid losses and loss adjustment expenses							$ 57,500
Minimum
Liability for Claims and Claims Adjustment Expense [Line Items]
Reinsurance retention policy, co-participation (percentage)			40.00%
Minimum | Adverse Development Cover Reinsurance Agreement
Liability for Claims and Claims Adjustment Expense [Line Items]
Reinsurance retention policy carried reserves threshold	$ 1,400
Unpaid losses and loss adjustment expenses							$ 36,600
Winter Storm Uri
Liability for Claims and Claims Adjustment Expense [Line Items]
Losses and loss adjustment expenses, net		$ 2,000
Commercial Line
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year adjustments			$ 18,500	15,200	7,600
Losses and loss adjustment expenses, net					(5,700)
Personal Line
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year adjustments			957,000,000	352,000,000	3,000
Hospitality
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year adjustments			12,000	12,000	11,000
Small Business Lines
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year adjustments			$ 6,500	$ 3,200	2,400
Florida Homeowners
Liability for Claims and Claims Adjustment Expense [Line Items]
Prior year adjustments					$ 1,700