Underwriting, Acquisition and Insurance Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Underwriting, Acquisition and Insurance Expenses [Abstract]
Gross commissions	$ 12,409	$ 9,517	$ 34,470	$ 26,652
Ceding commissions	(3,150)	(2,716)	(9,202)	(7,624)
Other operating expenses	9,065	7,049	25,109	19,739
Underwriting, acquisition, and insurance expenses	18,324	13,850	50,377	38,767
Salaries, bonuses and employee benefits	$ 7,300	$ 5,300	$ 21,200	$ 15,600