VARIABLE INTEREST ENTITY (Carrying Amount of VIE Consolidated Assets and Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Dec. 31, 2014
Investments
Debt securities, available for sale, at amortized cost	$ 370,881	$ 338,021
Equity securities, available-for-sale, at fair value	41,334	38,534
Total investments (including $28,290 and $22,670 related to the VIE, respectively)	426,093	384,331
Cash and cash equivalents	106,200	53,038	$ 76,161	$ 40,157
Prepaid reinsurance premiums	58,763	120,771
Premiums receivable, net	63,605	38,594
Income taxes receivable	16,706	2,691
Deferred acquisition costs	41,247	15,547
Other asset	7,829	7,605
TOTAL ASSETS	749,457	638,185
LIABILITIES
Loss and loss adjustment expense reserves	127,485	97,340		$ 78,330
Unearned premiums	309,283	253,960
Debt	4,903	4,887
Other liabilities	31,521	25,612
Total liabilities	486,104	387,426
Monarch Delaware - Variable Interest Entity [Member]
Investments
Debt securities, available for sale, at amortized cost	26,710	21,312
Equity securities, available-for-sale, at fair value	1,580	1,358
Total investments (including $28,290 and $22,670 related to the VIE, respectively)	28,290	22,670
Cash and cash equivalents	14,753	14,616
Prepaid reinsurance premiums		34
Premiums receivable, net	1,589	355
Other asset	1,269	1,037
TOTAL ASSETS	45,902	38,712
LIABILITIES
Loss and loss adjustment expense reserves	822	237
Unearned premiums	6,426	1,448
Debt	4,903	4,887
Income taxes payable		8
Other liabilities	1,461	374
Total liabilities	$ 13,612	$ 6,954