RENTAL PROPERTIES (Hamilton Green) (Details)					1 Months Ended	12 Months Ended
	Aug. 03, 2016 USD ($)	Sep. 18, 2015 USD ($) item	Mar. 02, 2005 USD ($)	Aug. 31, 2004 USD ($)	Aug. 31, 2014 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 item
RENTAL PROPERTIES
Number of units | item								1,033
Gain on sale of real estate						$ (104,443)
Hamilton Green
RENTAL PROPERTIES
Sales price of real estate properties	$ 1,000,000					$ 1,000,000
Gain on sale of real estate	103,793
Closing costs	227,663
Cost basis of the property	(668,544)
Prepayment penalty	$ 187,905
Residences at Captain Parkers LLC Residential Apartments Lexington, Massachusetts
RENTAL PROPERTIES
Number of units | item		94
Purchase price of real estate properties		$ 31,600,000
Purchase price allocated to the value of the in-place leases		474,000
Purchase price allocated to the value of the tenant relationships		$ 31,000
Amortization period of value of the in-place leases		12 months
Amortization period of value of the tenant relationships		24 months
Closing costs		$ 49,000
Hamilton on Main Apts
RENTAL PROPERTIES
Purchase price of real estate properties				$ 56,000,000
Hamilton 1025
RENTAL PROPERTIES
Purchase price of real estate properties			$ 23,750,000
Mortgage, 4.34%, August 2014 | Hamilton on Main Apts
RENTAL PROPERTIES
Closing costs							$ 161,000
Term of debt					10 years
Mortgage amount					$ 16,900,000
Interest rate (as a percent)					4.34%