SEGMENT INFORMATION - Net premiums earned by segment and lines of insurance (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenue from External Customer [Line Items]
Premiums earned	$ 127,188,280	$ 110,270,460	$ 247,685,532	$ 220,030,216
Property and casualty insurance [Member]
Revenue from External Customer [Line Items]
Premiums earned	97,816,887	87,825,285	190,521,905	172,856,675
Property and casualty insurance [Member] | Commercial Lines [Member]
Revenue from External Customer [Line Items]
Premiums earned	84,994,223	75,027,656	164,926,059	147,457,820
Property and casualty insurance [Member] | Commercial Lines [Member] | Automobile Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	21,097,112	19,053,727	41,220,711	36,909,397
Property and casualty insurance [Member] | Commercial Lines [Member] | Property Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	21,425,210	18,749,310	41,810,519	37,087,621
Property and casualty insurance [Member] | Commercial Lines [Member] | Workers Compensation Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	21,026,607	18,564,240	40,553,754	36,725,157
Property and casualty insurance [Member] | Commercial Lines [Member] | Liability Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	19,601,730	16,786,689	37,634,575	32,970,176
Property and casualty insurance [Member] | Commercial Lines [Member] | Other Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	1,843,564	1,873,690	3,706,500	3,765,469
Property and casualty insurance [Member] | Personal Lines [Member]
Revenue from External Customer [Line Items]
Premiums earned	12,822,664	12,797,629	25,595,846	25,398,855
Property and casualty insurance [Member] | Personal Lines [Member] | Automobile Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	6,917,799	7,119,459	13,839,379	14,094,368
Property and casualty insurance [Member] | Personal Lines [Member] | Property Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	5,728,302	5,524,351	11,415,785	11,002,952
Property and casualty insurance [Member] | Personal Lines [Member] | Liability Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	176,563	153,819	340,682	301,535
Reinsurance [Member]
Revenue from External Customer [Line Items]
Premiums earned	29,371,393	22,445,175	57,163,627	47,173,541
Reinsurance [Member] | Pro rata reinsurance [Member]
Revenue from External Customer [Line Items]
Premiums earned	10,305,013	5,455,122	20,205,152	13,844,025
Reinsurance [Member] | Pro rata reinsurance [Member] | Property And Liability Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	2,483,413	2,115,547	3,512,470	3,562,142
Reinsurance [Member] | Pro rata reinsurance [Member] | Property Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	3,644,882	4,308,272	8,271,643	6,767,632
Reinsurance [Member] | Pro rata reinsurance [Member] | Liability Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	1,125,276	295,324	1,517,955	639,376
Reinsurance [Member] | Pro rata reinsurance [Member] | Crop Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	506,046	195,609	946,407	472,559
Reinsurance [Member] | Pro rata reinsurance [Member] | Marine And Aviation Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	2,545,396	(1,459,630)	5,956,677	2,402,316
Reinsurance [Member] | Excess of loss reinsurance [Member]
Revenue from External Customer [Line Items]
Premiums earned	19,066,380	16,990,053	36,958,475	33,329,516
Reinsurance [Member] | Excess of loss reinsurance [Member] | Property Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	16,227,759	13,770,698	31,448,516	27,314,458
Reinsurance [Member] | Excess of loss reinsurance [Member] | Liability Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	2,838,621	3,218,590	5,509,903	6,006,901
Reinsurance [Member] | Excess of loss reinsurance [Member] | Fidelity And Surety Insurance L O B [Member]
Revenue from External Customer [Line Items]
Premiums earned	$ 0	$ 765	$ 56	$ 8,157