Effects of Reinsurance on Premiums (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Insurance [Abstract]
Direct Premiums Written	$ 708,252	$ 548,916	$ 417,769
Assumed Premiums Written	(96)	20,820	18,984
Ceded Premiums Written	(262,340)	(183,808)	(144,404)
Premiums Written, Net	445,816	385,928	292,349
Increase (Decrease) in Direct Unearned Premiums	(57,759)	(65,300)	(38,995)
Increase (Decrease) in Assumed Unearned Premiums	16,432	(221)	2,937
Increase (Decrease) in Ceded Unearned Premiums	52,442	15,551	8,559
Increase (Decrease) in Unearned Premiums	11,115	(49,970)	(27,499)
Direct Premiums Earned, Property and Casualty	650,493	483,616	378,774
Assumed Premiums Earned, Property and Casualty	16,336	20,599	21,921
Ceded Premiums Earned	(209,898)	(168,257)	(135,845)
Premiums Earned, Net	456,931	335,958	264,850
Direct Losses and LAE Incurred	335,542	188,270	111,820
Assumed Losses and LAE Incurred	3,747	7,861	8,672
Ceded Losses and LAE Incurred	(40,936)	(13,023)	(2,415)
Net Losses and LAE Incurred	$ 298,353	$ 183,108	$ 118,077