IMPAIRMENT OF LONG-LIVED ASSETS (Details)	3 Months Ended				9 Months Ended		12 Months Ended
	Jun. 30, 2017 a	Mar. 31, 2017 a	Sep. 30, 2016 a	Mar. 31, 2016 a	Sep. 30, 2017 USD ($) a	Sep. 30, 2016 USD ($) a	Dec. 31, 2016 USD ($) a
Impairment of Long-Lived Assets
Impairment Charges						$ 2,180,730
Acres sold | a	81.43	1,587.35	4.5	7.5	1,668.78	12.0
2016 dispositions of income property subject to a lease | September 2016 disposition of income property subject to a lease
Impairment of Long-Lived Assets
Impairment Charges						$ 942,000
Impairment charge						783,000
Closing costs						159,000
2016 dispositions of income property subject to a lease | April 2016 disposition of income property subject to a lease
Impairment of Long-Lived Assets
Impairment Charges						210,000
Impairment charge						134,000
Closing costs						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
Anticipated loss on the sale						$ 646,000
Estimated closing costs						71,000
Four acres of undeveloped land, one | Land Under Contract for Sale
Impairment of Long-Lived Assets
Impairment Charges						$ 717,000
Acres sold | a						4
Four acres of undeveloped land, two
Impairment of Long-Lived Assets
Estimated closing costs						$ 55,000
Four acres of undeveloped land, two | Land Under Contract for Sale
Impairment of Long-Lived Assets
Impairment Charges						$ 311,000
Acres sold | a						4
Anticipated loss on the sale						$ 256,000