Schedule VI - Supplemental Information Concerning Insurance Operations - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Premiums Written, Net	$ 342,893	$ 319,499	$ 225,254
Earned premiums		261,369	213,020
Net investment income		9,063	7,226
Claim and claim adjustment expenses incurred related to current year	245,545	201,704	120,005
Claim and claim adjustment expenses incurred related to prior year	2,012	(3,894)	(7,295)
Property and Casualty Insurance [Member]
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Deferred acquisition costs	40,893	41,892	17,666
Loss and loss adjustment expense reserves	230,515	158,110	97,706
Unearned premiums	294,423	294,022	253,960
Earned premiums	333,481
Net investment income	10,254
Claim and claim adjustment expenses incurred related to current year	245,545	201,704	120,005
Claim and claim adjustment expenses incurred related to prior year	2,012	(3,894)	(7,295)
Supplemental Information for Property, Casualty Insurance Underwriters, Amortization of Deferred Policy Acquisition Costs	87,310	57,452	31,340
Paid claims and claims adjustment expense	233,085	170,322	90,436
Supplemental Information for Property, Casualty Insurance Underwriters, Premiums Written	$ 342,893	$ 319,499	$ 225,254