Liability for Unpaid Losses and Loss Adjustment Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Liability for Claims and Claims Adjustment Expense [Line Items]
Current Year Claims and Claims Adjustment Expense	$ 404,271	$ 368,148	$ 281,365
Prior Year Claims and Claims Adjustment Expense	(4,318)	2,613	16,988
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims	408,589	365,535	298,353
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year	283,821	256,134	210,970
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years	117,994	95,272	62,506
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid	401,815	351,406	273,476
Liability for Unpaid Claims and Claims Adjustment Expense, Net	183,333	176,559	122,131
Reinsurance Recoverable on Unpaid Losses and LAE			18,724	$ 2,114
Liability for Unpaid Claims and Claims Adjustment Expense, Net, Including Acquisition		176,559	122,131	74,678
Unpaid losses and loss adjustment expenses	661,203	482,232	140,855	$ 76,792
Liability for Unpaid Claims and Claims Adjustment Expense, Reported Claims, Amount	270,601	236,253	83,447
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred but Not Reported (IBNR) Claims, Amount	$ 390,602	$ 245,979	$ 57,408