RENTAL PROPERTIES (Reconciliation) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Rental Properties
Balance, Beginning	$ 261,276,898	$ 225,021,946
Additions:
Buildings, improvements and other assets	5,163,081	37,895,926	$ 5,604,791
Balance before deductions	266,439,979	262,917,872	227,059,077
Deduct:
Write-offs of retired or disposed assets	2,112,142	1,640,974	2,037,131
Rental properties held for sale and/or sold	668,544
Balance, Ending	263,659,293	261,276,898	225,021,946
Accumulated Depreciation
Balance, Beginning	84,579,584	75,905,862
Add:
Depreciation for the year	11,729,039	10,314,696	9,393,368
Total additions	96,308,623	86,220,558	77,942,993
Deduct:
Accumulated depreciation of retired or disposed assets	2,112,141	1,640,974	2,037,131
Balance, Ending	$ 94,196,482	$ 84,579,584	$ 75,905,862