Segment Information - Information by Reportable Operating Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Segment Reporting Information [Line Items]
Gross written premiums	$ 23,737	$ 26,474
Net written premiums	19,845	22,324
Net earned premiums	23,800	24,140
Other income	357	354
Segment revenue	24,157	24,494
Losses and loss adjustment expenses, net	13,328	15,733
Policy acquisition costs	6,513	6,472
Operating expenses	4,187	4,530
Segment expenses	24,028	26,735
Segment underwriting gain (loss)	129	(2,241)
Net investment income	802	577
Net realized investment gains (losses)	161	(8)
Change in fair value of equity securities	(297)	0
Interest expense	(619)	(224)
Income (loss) before equity earnings of affiliates and income taxes	176	(1,896)
Operating Segments | Commercial Lines
Segment Reporting Information [Line Items]
Gross written premiums	21,788	21,644
Net written premiums	19,422	19,479
Net earned premiums	20,127	19,689
Other income	143	164
Segment revenue	20,270	19,853
Losses and loss adjustment expenses, net	10,200	12,468
Policy acquisition costs	5,442	5,022
Operating expenses	3,498	2,472
Segment expenses	19,140	19,962
Segment underwriting gain (loss)	1,130	(109)
Operating Segments | Personal Lines
Segment Reporting Information [Line Items]
Gross written premiums	1,949	4,830
Net written premiums	423	2,845
Net earned premiums	3,673	4,451
Other income	180	151
Segment revenue	3,853	4,602
Losses and loss adjustment expenses, net	3,128	3,265
Policy acquisition costs	1,071	1,450
Operating expenses	370	569
Segment expenses	4,569	5,284
Segment underwriting gain (loss)	(716)	(682)
Corporate & Other
Segment Reporting Information [Line Items]
Gross written premiums	0	0
Net written premiums	0	0
Net earned premiums	0	0
Other income	34	39
Segment revenue	34	39
Losses and loss adjustment expenses, net	0	0
Policy acquisition costs	0	0
Operating expenses	319	1,489
Segment expenses	319	1,489
Segment underwriting gain (loss)	(285)	(1,450)
Net investment income	802	577
Net realized investment gains (losses)	161	(8)
Change in fair value of equity securities	(297)
Interest expense	(619)	(224)
Income (loss) before equity earnings of affiliates and income taxes	$ (238)	$ (1,105)