Summary of Significant Accounting Policies - Summary of Deferred Policy Acquisition Cost Amortization and Net Advertising Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accounting Policies [Abstract]
Deferred policy acquisition cost amortization	$ 708,525	$ 654,612	$ 633,385
Net advertising expense	$ 8,900	$ 11,800	$ 50,100