Description of Business and Summary of Significant Accounting Policies - Deferred Policy Acquisition Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Accounting Policies [Abstract]
Amortization expense	$ 8.2	$ 15.7	$ 31.3	$ 34.3