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MORTGAGE NOTES PAYABLE AND LINE OF CREDIT (Details)				1 Months Ended	6 Months Ended
MORTGAGE NOTES PAYABLE AND LINE OF CREDIT (Details)	Jul. 31, 2014 USD ($) item	Jul. 11, 2014 USD ($)	Jun. 11, 2014 USD ($)	Feb. 28, 2014 USD ($)	Jun. 30, 2015 USD ($) shares	Jun. 30, 2014 shares
MORTGAGE NOTES PAYABLE
Effective interest rate (as a percent)					5.36%
Annual maturities of mortgage debt
2016-current maturities					$ 504,000
2017					1,629,000
2018					1,821,000
2019					7,900,000
2020					4,330,000
Thereafter					179,822,000
Total					196,006,000
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months					504,000
Additional disclosures related to mortgages
Amount of new loan					8,042,000
Repurchase of depository receipts					$ 1,505,645
Repurchase of units \| shares					1,253	664
Commitment fee for unused line of credit					$ 25,000
Line of Credit
Additional disclosures related to mortgages
Term of debt	3 years
Maximum borrowings	$ 25,000,000
Funds drawn by the company					0
Number of properties in which borrowing amount collateralized \| item	23
Amount of refinancing costs	$ 125,000
Base Rate [Member] \| Line of Credit
Additional disclosures related to mortgages
Reference rate used in calculation of Base Rate	base
Prime Rate [Member] \| Line of Credit
Additional disclosures related to mortgages
Reference rate used in calculation of Base Rate	Prime
Federal Funds Rate [Member] \| Line of Credit
Additional disclosures related to mortgages
Basis of effective interest rate used in calculation of Base Rate (as a percent)	0.50%
Reference rate used in calculation of Base Rate	Federal Funds
London Interbank Offered Rate (LIBOR) [Member] \| Line of Credit
Additional disclosures related to mortgages
Basis of effective interest rate used in calculation of Base Rate (as a percent)	1.00%
Reference rate used in calculation of Base Rate	one month LIBOR
Minimum \| Line of Credit
Additional disclosures related to mortgages
Commitment fee for unused amount (as a percent)	0.15%
Pledged interests rate of the Partnership's ownership interest (as a percent)	49.00%
Minimum \| Base Rate [Member] \| Line of Credit
Additional disclosures related to mortgages
Debt Instrument, Basis Spread on Variable Rate	2.50%
Maximum \| Line of Credit
Additional disclosures related to mortgages
Commitment fee for unused amount (as a percent)	0.20%
Pledged interests rate of the Partnership's ownership interest (as a percent)	100.00%
Maximum \| Base Rate [Member] \| Line of Credit
Additional disclosures related to mortgages
Debt Instrument, Basis Spread on Variable Rate	3.50%
Mortgages payable
MORTGAGE NOTES PAYABLE
Amount of monthly installments including principal					$ 808,000
Weighted average interest rate (as a percent)					4.81%
Effective interest rate (as a percent)					4.93%
Additional disclosures related to mortgages
Mortgage prepayment penalties				$ 0
Mortgages payable \| NERA Dean Street Associates, LLC
MORTGAGE NOTES PAYABLE
Interest rate (as a percent)			4.22%
Additional disclosures related to mortgages
Amount of new loan			$ 5,687,000
Period of interest only payments on loans			10 years
Amount of loan proceeds utilized for pay off the existing mortgage			$ 5,077,000
Refinancing cost			$ 89,000
Mortgages payable \| Hamilton Linewt LLC Commercial-1031Exchange Newton, Massachusetts
Additional disclosures related to mortgages
Amount of mortgage paid off				1,466,000
Mortgages payable \| Linhart L.P. Residential/Commercial Newton, Massachusetts
Additional disclosures related to mortgages
Amount of mortgage paid off				$ 1,926,000
Mortgages payable \| Courtyard At Westgate Residential Units Burlington Massachusetts Member
MORTGAGE NOTES PAYABLE
Interest rate (as a percent)		4.31%
Additional disclosures related to mortgages
Period of interest only payments on loans		10 years
Amount of loan proceeds utilized for pay off the existing mortgage		$ 2,010,000
Amount of new loan		2,500,000
Amount of refinancing costs		$ 75,000
Mortgages payable \| Minimum
MORTGAGE NOTES PAYABLE
Interest rate (as a percent)					3.76%
Mortgages payable \| Maximum
MORTGAGE NOTES PAYABLE
Interest rate (as a percent)					5.97%