Deferred Reinsurance Ceding Commission - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Policy Acquisition Costs [Member]
Deferred Reinsurance Ceding Commission [Line Items]
Ceding commission income	$ 11.5	$ 11.9	$ 23.2	$ 23.2
General and Administrative Expenses [Member]
Deferred Reinsurance Ceding Commission [Line Items]
Ceding commission income	$ 3.9	$ 3.9	$ 7.7	$ 7.6