Reinsurance - Effects of Reinsurance and Assumption Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Written premiums:
Direct	$ 16,814	$ 20,112	$ 53,237	$ 61,731
Assumed	9,815	9,469	23,691	21,305
Ceded	(3,783)	(11,186)	(11,642)	(19,235)
Net written premiums	22,846	18,395	65,286	63,801
Earned premiums:
Direct	19,955	21,797	61,739	65,817
Assumed	7,363	7,094	21,160	19,676
Ceded	(3,868)	(11,232)	(11,711)	(19,198)
Net earned premiums	23,450	17,659	71,188	66,295
Losses and LAE:
Direct	19,324	27,268	46,714	59,496
Assumed	5,027	5,313	11,996	14,017
Ceded	(7,797)	(6,113)	(13,760)	(14,638)
Total net incurred losses and LAE	$ 16,554	$ 26,468	$ 44,950	$ 58,875