Reinsurance - Effect of Reinsurance on Net Premiums Written and Earned (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Net premiums written        
Direct $ 46,672 $ 48,862 $ 85,916 $ 86,991
Ceded (6,886) 0 (11,527) 0
Net premiums written 39,786 48,862 74,389 86,991
Net premiums earned        
Direct 44,233 26,041 81,671 45,848
Ceded (6,316) 0 (10,529) 0
Net premiums earned $ 37,917 $ 26,041 $ 71,142 $ 45,848