LOSS AND LOSS ADJUSTMENT RESERVES - (Schedule of Reconciliation of Net Incurred and Paid Development) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Liability for Claims and Claims Adjustment Expense [Abstract]
Total liabilities for unpaid losses and LAE, net of reinsurance	$ 125,541	$ 127,791
Reinsurance Recoverables on Unpaid Losses, Gross to Net [Abstract]
Total reinsurance recoverables	166,396	98,345
Unallocated loss adjustment expenses	4,293	4,379
Unfavorable loss and LAE reserve	296,230	230,515	$ 158,110	$ 97,706
Homeowners [Member]
Liability for Claims and Claims Adjustment Expense [Abstract]
Total liabilities for unpaid losses and LAE, net of reinsurance	102,279	99,650
Reinsurance Recoverables on Unpaid Losses, Gross to Net [Abstract]
Total reinsurance recoverables	158,043	81,852
Unfavorable loss and LAE reserve	102,279
Commercial General Liability [Member]
Liability for Claims and Claims Adjustment Expense [Abstract]
Total liabilities for unpaid losses and LAE, net of reinsurance	18,888	17,111
Reinsurance Recoverables on Unpaid Losses, Gross to Net [Abstract]
Total reinsurance recoverables	0	0
Unfavorable loss and LAE reserve	18,888
Personal Auto Liability [Member]
Liability for Claims and Claims Adjustment Expense [Abstract]
Total liabilities for unpaid losses and LAE, net of reinsurance	4,374	11,030
Reinsurance Recoverables on Unpaid Losses, Gross to Net [Abstract]
Total reinsurance recoverables	8,275	15,360
Unfavorable loss and LAE reserve	4,374
Flood Insurance [Member]
Liability for Claims and Claims Adjustment Expense [Abstract]
Total liabilities for unpaid losses and LAE, net of reinsurance	0	0
Reinsurance Recoverables on Unpaid Losses, Gross to Net [Abstract]
Total reinsurance recoverables	$ 78	$ 1,133