INCOME TAXES - Sources of Deferred Income Tax Assets (Liabilities) (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Deferred Income Tax Assets
Depreciation	$ 4,785,992	$ 4,904,976
Intangible Lease Liabilities	6,503,574	7,111,608
Income Property Lease Incentive	732,172	1,069,882
Impairment Reserves	92,751	1,393,415
Stock Options and Restricted Stock	1,274,694	977,210
Capital Loss Carryforward	20,750	20,750
Deferred Oil Lease Income		121,323
Other - Net	6,638	44,967
Gross Deferred Income Tax Assets	13,416,571	15,644,131
Less - Valuation Allowance	(272,966)	(272,966)
Net Deferred Income Tax Assets	13,143,605	15,371,165
Deferred Income Tax Liabilities
Sales of Real Estate	(87,353,465)	(67,388,733)
Income Property Tenant Contributions		(606,820)
Discount on Equity Component of Convertible Debt	(42,400)	(238,200)
Basis Difference in Joint Venture	(11,789,044)	(764,566)
Basis Difference in Alpine Income Property OP, LP	(3,979,966)
Interest Rate Swap	(73,924)	(486,543)
Deferred Revenue (Net of Straight-line Rent Adjustments)	(186,979)	(578,034)
Other - Net		(78,176)
Total Deferred Income Tax Liabilities	(103,425,778)	(70,141,072)
Net Deferred Income Tax Liabilities	$ (90,282,173)	$ (54,769,907)