CASH FLOW INFORMATION (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash paid for interest	$ 9,942,000	$ 9,838,000	$ 8,791,000
Cash paid for state income taxes	$ 47,000	32,000	51,000
NERA Dean Street Apartments And Westgate Apartments
Non-cash financing activities in connection with acquisition			$ 7,077,000
Residences at Captain Parkers LLC Residential Apartments Lexington, Massachusetts
Non-cash financing activities in connection with acquisition		$ 25,000,000