INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Details) (USD $)	9 Months Ended			0 Months Ended	9 Months Ended		0 Months Ended					1 Months Ended					1 Months Ended			1 Months Ended			9 Months Ended			1 Months Ended	9 Months Ended					0 Months Ended		1 Months Ended				1 Months Ended								9 Months Ended	12 Months Ended					1 Months Ended																0 Months Ended					1 Months Ended		3 Months Ended	12 Months Ended			0 Months Ended					1 Months Ended		3 Months Ended		9 Months Ended				9 Months Ended				9 Months Ended
	Sep. 30, 2013 item	Sep. 30, 2012	Dec. 31, 2012	Oct. 28, 2009 Dexter Park item	Sep. 30, 2013 Dexter Park item	Sep. 30, 2012 Dexter Park	Oct. 28, 2009 Dexter Park Mortgage loan	Sep. 30, 2013 Dexter Park Mortgage loan	Sep. 30, 2013 Hamilton Bay Apartments, LLC item	Sep. 30, 2012 Hamilton Bay Apartments, LLC	Oct. 03, 2005 Hamilton Bay Apartments, LLC item	Feb. 28, 2007 Hamilton Bay Apartments, LLC Mortgage loan	Sep. 30, 2013 Hamilton Bay Apartments, LLC Mortgage loan	Sep. 30, 2013 Hamilton Bay Sales item	Sep. 30, 2012 Hamilton Bay Sales item	Apr. 30, 2008 Hamilton Bay Sales item	Apr. 30, 2008 Hamilton Bay Sales Mortgage loan	Sep. 30, 2013 Hamilton Bay Sales Mortgage loan	Mar. 07, 2005 Hamilton Essex Development, LLC and Hamilton Essex 81, LLC	Mar. 31, 2005 Hamilton Essex Development, LLC and Hamilton Essex 81, LLC Mortgage loan	Sep. 30, 2013 Hamilton Essex 81, LLC item	Sep. 30, 2012 Hamilton Essex 81, LLC	Sep. 30, 2013 Hamilton Essex 81, LLC Mortgage loan	Sep. 30, 2013 Hamilton Essex Development, LLC item	Sep. 30, 2012 Hamilton Essex Development, LLC	Sep. 30, 2013 Hamilton Essex Development, LLC Mortgage loan	Sep. 30, 2013 Hamilton Essex Development, LLC Mortgage loan	Aug. 31, 2008 Hamilton Essex Development, LLC Mortgage loan	Sep. 30, 2013 Hamilton 1025, LLC item	Sep. 30, 2012 Hamilton 1025, LLC	Mar. 02, 2005 Hamilton 1025, LLC item	Mar. 02, 2005 Hamilton 1025, LLC Mortgage loan	Sep. 30, 2013 Hamilton 1025, LLC Mortgage loan	Oct. 31, 2004 Hamilton Minuteman, LLC	Sep. 30, 2013 Hamilton Minuteman, LLC item	Sep. 30, 2012 Hamilton Minuteman, LLC	Sep. 30, 2004 Hamilton Minuteman, LLC item	Jan. 31, 2007 Hamilton Minuteman, LLC Mortgage loan	Oct. 31, 2004 Hamilton Minuteman, LLC Mortgage loan	Sep. 30, 2013 Hamilton Minuteman, LLC Mortgage loan	Dec. 31, 2006 Hamilton Minuteman, LLC Mortgage loan	Sep. 30, 2013 Hamilton Place item	Sep. 30, 2012 Hamilton Place	May 31, 2008 Hamilton Place item	Aug. 31, 2004 Hamilton Place item	Sep. 30, 2013 Hamilton on Main Apartments, LLC	Dec. 31, 2005 Hamilton on Main Apartments, LLC Mortgage loan item	Sep. 30, 2013 Hamilton on Main Apartments, LLC Mortgage loan	Sep. 30, 2013 345 Franklin, LLC item	Sep. 30, 2012 345 Franklin, LLC	Nov. 30, 2001 345 Franklin, LLC item	Jun. 30, 2013 345 Franklin, LLC Mortgage loan	Sep. 30, 2013 345 Franklin, LLC Mortgage loan	Sep. 30, 2013 Residential buildings Dexter Park item	Sep. 30, 2013 Residential buildings Hamilton Bay Apartments, LLC item	Sep. 30, 2013 Residential buildings Hamilton Bay Sales item	Sep. 30, 2013 Residential buildings Hamilton Essex 81, LLC item	Sep. 30, 2013 Residential buildings Hamilton 1025, LLC item	Sep. 30, 2013 Residential buildings Hamilton Minuteman, LLC item	Sep. 30, 2013 Residential buildings Hamilton Place item	Sep. 30, 2013 Residential buildings 345 Franklin, LLC item	Mar. 07, 2005 Apartment Hamilton Essex Development, LLC and Hamilton Essex 81, LLC Mortgage loan item	Mar. 07, 2005 Commercial Hamilton Essex Development, LLC and Hamilton Essex 81, LLC item	Sep. 30, 2013 Commercial Hamilton Essex 81, LLC item	Sep. 30, 2013 Commercial Hamilton Essex Development, LLC item	Sep. 30, 2013 Commercial Hamilton 1025, LLC item	Mar. 07, 2005 Car parking lot Hamilton Essex Development, LLC and Hamilton Essex 81, LLC item	Dec. 15, 2011 HBC	Oct. 01, 2011 HBC	Aug. 01, 2011 HBC	Aug. 17, 2010 HBC	Oct. 28, 2009 HBC	Apr. 30, 2012 HBC	Feb. 29, 2012 HBC	Dec. 31, 2010 HBC	Dec. 31, 2012 HBC	Dec. 31, 2011 HBC	Dec. 31, 2011 HBC Mortgage loan	Dec. 15, 2011 HBC Dexter Park Mortgage loan	Oct. 01, 2011 HBC Dexter Park Mortgage loan	Aug. 01, 2011 HBC Dexter Park Mortgage loan	Aug. 17, 2010 HBC Dexter Park Mortgage loan	Oct. 28, 2009 HBC Dexter Park Mortgage loan	Apr. 30, 2012 HBC Dexter Park Mortgage loan	Feb. 29, 2012 HBC Dexter Park Mortgage loan	Mar. 31, 2012 HBC Dexter Park Mortgage loan	Dec. 31, 2010 HBC Dexter Park Mortgage loan	Sep. 30, 2013 HBC Dexter Park Mortgage loan	Sep. 30, 2013 Management Company item	Sep. 30, 2013 Minimum Mortgage loan	Sep. 30, 2013 Minimum Limited Partnerships	Sep. 30, 2013 Minimum Hamilton on Main Apartments, LLC	Sep. 30, 2013 Minimum Harold Brown	Sep. 30, 2013 Maximum Mortgage loan	Sep. 30, 2013 Maximum Limited Partnerships	Sep. 30, 2013 Maximum Hamilton on Main Apartments, LLC	Sep. 30, 2013 Maximum Harold Brown
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of limited partnerships and limited liability companies in which the entity has invested	9
Number of partnerships investing in commercial property	3
Percentage of ownership interest				40.00%							50.00%								50.00%												50.00%						50.00%								50.00%						50.00%																																								40.00%		43.20%		50.00%		57.00%
Number of employees having ownership interest																																																																																									5
Investments in joint venture	$ 10,652,571		$ 13,986,173	$ 15,925,000							$ 2,500,000								$ 2,000,000												$ 2,352,000						$ 5,075,000								$ 8,000,000						$ 1,533,000
Number of units				409	409				48		168			120		20					49			1					176		176				42		42					148			280				40		40			409	48	120	48	175	42	148	40	49		1	1	1
Number of properties																																																															1
Purchase price of investments				129,500,000							30,875,000								14,300,000												23,750,000						10,100,000								56,000,000
Borrowings							89,914,000					4,750,000					2,368,000			10,750,000			8,264,000				2,054,000					5,000,000						5,500,000	8,025,000								16,825,000																									7,168,000											7,168,000
Interest rate (as a percent)							5.57%					5.57%					5.75%						5.79%									5.67%						5.67%									5.18%					3.87%																				6.00%											6.00%							2.44%				7.07%
Period for which the entity is required to make interest only payments							2 years					5 years																				5 years						5 years									3 years					3 years
Amortization period of debt							30 years					30 years											30 years									30 years						30 years									30 years					30 years
Outstanding amount of mortgage loan	191,974,239		138,055,522		87,707,013	88,891,126		87,707,000	4,655,194	4,716,555			4,655,000	1,318,000	1,668,000			1,318,000			8,263,635	8,379,679		2,054,475	2,106,087				4,885,643	4,949,865			4,886,000		5,379,695	5,450,034				5,380,000		15,390,766	15,680,318					15,391,000	10,000,000	6,893,510			10,000,000																								1,668,600	1,668,600
Investments funded using cash reserves				8,757,000
Term of debt																																10 years						10 years									10 years					15 years																				4 years											4 years
Notice period for principal paydown of debt																																																																								6 months											6 months
Principal amount requested to be repaid																																																																							2,500,000											2,500,000
Repayment of loan																																																																									918,600		2,500,000									918,600			2,500,000
Principal payments elected to be made																																																																				1,000,000	1,000,000	1,000,000				750,000					1,000,000	1,000,000	1,000,000				750,000
Interest paid	5,795,000	5,854,000																																																																										18,960										18,807		0
Amortization period of intangible assets					12 months
Number of units retained for long-term investment					409				48		48										49			1					49		49				42							148					3		40
Number of units retained														15	15
Number of units sold	0													105															127		127													137
Units to be sold														120															127
Capacity of real estate property (in cars per lot)																																																																			50
Margin over basis of interest rate (as a percent)																										2.25%	2.25%
Basis of interest rate																											Libor
Notional margin over basis of interest rate (as a percent)																										0.1789%	0.1789%
Principal amount of debt to be paid per month																										4,443	4,301
Cost associated with loan extension																										9,000	6,000
Extended term of debt																										2 years
Maximum personal guaranty on mortgage																												1,000,000
Amount returned to partnership																																		3,775,000
Cash contribution by the entity towards loan																																									1,250,000
Ownership percentage in third party entity by majority shareholder of the General Partner																																														31.00%
Ownership percentage in third party entity by President of management company																																														5.00%
Percentage of variable commission on each sale																																																																																												3.00%				5.00%
Term excluding period for which interest only payments to be made																																															7 years
Net proceeds after funding escrow accounts and closing costs																																															16,700,000
Fee for early extinguishment of debt																																															400,000
Refinanced amount																																																				$ 10,000,000