Underwriting, Acquisition and Insurance Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Underwriting, Acquisition and Insurance Expenses [Abstract]
Gross commissions	$ 21,165	$ 15,142
Ceding commissions	(5,355)	(3,183)
Other operating expenses	12,326	9,624
Underwriting, acquisition, and insurance expenses	28,136	21,583
Salaries, bonuses and employee benefits	$ 11,300	$ 8,800