IMPAIRMENT OF LONG-LIVED ASSETS (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016 USD ($) a	Mar. 31, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($) a	Dec. 31, 2016 USD ($) a
Impairment of Long-Lived Assets
Impairment Charges	$ 1,970,822			$ 2,180,730
2016 dispositions of income property subject to a lease | Under contract to be sold
Impairment of Long-Lived Assets
Impairment Charges	942,000	$ 210,000		942,000
Loss on the sale	783,000	134,000
Closing costs	$ 159,000	$ 76,000
Undeveloped Land
Impairment of Long-Lived Assets
Impairment Charges			$ 0	$ 1,000,000
Undeveloped Land | Land Under Contract for Sale
Impairment of Long-Lived Assets
Impairment Charges					$ 1,000,000
Area of Land | a	6			6	8
Four acres of undeveloped land, one
Impairment of Long-Lived Assets
Impairment Charges	$ 717,000
Area of Land | a	4			4
Anticipated loss on the sale	$ 646,000
Estimated closing costs	71,000
Four acres of undeveloped land, two
Impairment of Long-Lived Assets
Impairment Charges	$ 311,000
Area of Land | a	4			4
Anticipated loss on the sale	$ 256,000
Estimated closing costs	$ 55,000,000