REAL ESTATE AFFILIATES (Details) (USD $)	3 Months Ended		9 Months Ended			3 Months Ended		9 Months Ended			3 Months Ended	9 Months Ended			9 Months Ended		0 Months Ended					3 Months Ended	9 Months Ended			1 Months Ended				3 Months Ended	9 Months Ended				1 Months Ended						3 Months Ended		9 Months Ended			3 Months Ended	9 Months Ended			3 Months Ended		9 Months Ended			1 Months Ended				1 Months Ended	9 Months Ended				1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Sep. 30, 2012 Equity method investments	Sep. 30, 2011 Equity method investments	Sep. 30, 2012 Equity method investments	Sep. 30, 2011 Equity method investments	Dec. 31, 2011 Equity method investments	Sep. 30, 2011 Cost basis investments	Sep. 30, 2012 Cost basis investments	Sep. 30, 2011 Cost basis investments	Dec. 31, 2011 Cost basis investments	Sep. 30, 2011 The Woodlands Equity method investments	Jun. 30, 2011 The Woodlands Equity method investments	Oct. 30, 2012 Bridges at Mint Hill, LLC	Sep. 30, 2012 Bridges at Mint Hill, LLC Equity method investments	Dec. 31, 2011 Bridges at Mint Hill, LLC Equity method investments	Sep. 30, 2012 Circle T Equity method investments	Dec. 31, 2011 Circle T Equity method investments	Sep. 30, 2011 Forest View Apartments Equity method investments	Sep. 30, 2012 Forest View Apartments Equity method investments	Sep. 30, 2011 Forest View Apartments Equity method investments	Dec. 31, 2011 Forest View Apartments Equity method investments	Oct. 31, 2011 HHMK Development, LLC item	Sep. 30, 2012 HHMK Development, LLC Equity method investments	Dec. 31, 2011 HHMK Development, LLC Equity method investments	May 31, 2012 Millennium Waterway Apartments	Sep. 30, 2011 Millennium Waterway Apartments Equity method investments	Sep. 30, 2012 Millennium Waterway Apartments Equity method investments	Sep. 30, 2011 Millennium Waterway Apartments Equity method investments	May 14, 2012 Millennium Waterway Apartments Equity method investments	Dec. 31, 2011 Millennium Waterway Apartments Equity method investments	Jul. 31, 2012 Millennium Woodlands Phase II, LLC. Acres	May 31, 2012 Millennium Woodlands Phase II, LLC. item	May 14, 2012 Millennium Woodlands Phase II, LLC.	Sep. 30, 2012 Millennium Woodlands Phase II, LLC. Equity method investments	Sep. 30, 2012 Parcel D Development, LLC Equity method investments	Dec. 31, 2011 Parcel D Development, LLC Equity method investments	Sep. 30, 2012 Stewart Title Equity method investments	Sep. 30, 2011 Stewart Title Equity method investments	Sep. 30, 2012 Stewart Title Equity method investments	Sep. 30, 2011 Stewart Title Equity method investments	Dec. 31, 2011 Stewart Title Equity method investments	Sep. 30, 2011 Timbermill Apartments Equity method investments	Sep. 30, 2012 Timbermill Apartments Equity method investments	Sep. 30, 2011 Timbermill Apartments Equity method investments	Dec. 31, 2011 Timbermill Apartments Equity method investments	Sep. 30, 2012 Woodlands Sarofim # 1 Equity method investments	Sep. 30, 2011 Woodlands Sarofim # 1 Equity method investments	Sep. 30, 2012 Woodlands Sarofim # 1 Equity method investments	Sep. 30, 2011 Woodlands Sarofim # 1 Equity method investments	Dec. 31, 2011 Woodlands Sarofim # 1 Equity method investments	Apr. 30, 2012 Forest View/Timbermill Apartments	Sep. 30, 2012 Properties owned by real estate affiliates	Sep. 30, 2012 Properties owned by real estate affiliates Millennium Woodlands Phase II, LLC.	Sep. 30, 2012 Properties owned by real estate affiliates Woodlands Sarofim # 1	Sep. 30, 2012 KR Holdings, LLC	Sep. 30, 2012 KR Holdings, LLC	Sep. 17, 2012 KR Holdings, LLC	Sep. 30, 2012 KR Holdings, LLC Equity method investments	Sep. 30, 2012 KR Holdings, LLC Properties owned by real estate affiliates	Sep. 30, 2012 KR Holdings, LLC Mezzanine loan agreements item	Sep. 17, 2012 KR Holdings, LLC Mezzanine loan agreements
Real Estate Affiliates
Number of local developers with whom the entity entered into a joint venture																										2
Ownership ratio in a joint venture																																																												50.00%
Number of debt instruments																																																																2
Amount of borrowings																																																																$ 20,000,000
Blended interest rate (as a percent)																																																																	12.00%
Option to extend, term																																																																1 year
Preferred return on capital (as a percent)																																																											13.00%
Committed pre-development costs																																																																	3,000,000
Committed pre-development costs																																																													40,000,000
Funded pre-development costs																																																																2,000,000
Investment in Real Estate Affiliates
Economic ownership (as a percent)																52.50%	90.50%	79.00%	79.00%	50.00%	50.00%				50.00%		50.00%	50.00%	100.00%		100.00%		18.57%	83.55%				81.43%	50.00%	50.00%	50.00%		50.00%		50.00%				50.00%	20.00%		20.00%		20.00%								50.00%
Carrying Value	36,162,000		36,162,000		62,595,000	23,418,000		23,418,000		49,617,000		12,744,000		12,978,000				673,000	180,000	9,004,000	9,004,000				5,358,000		947,000							21,998,000				2,190,000	4,084,000	2,990,000	3,758,000		3,758,000		3,643,000				3,988,000	2,462,000		2,462,000		2,456,000
Share of Earnings	310,000	166,000	3,432,000	7,787,000		310,000	131,000	1,056,000	3,858,000		35,000	2,376,000	3,929,000		3,727,000							1,000	2,000	1,000						14,000	406,000	14,000									324,000	85,000	640,000	85,000		1,000	2,000	1,000		(14,000)	30,000	6,000	30,000
Aggregate carrying value of unconsolidated VIEs	7,900,000		7,900,000		3,200,000
Number of units in Class A multi-family unit in The Woodlands Town Center to be constructed																																				314
Amount funded in cash to joint venture																	4,500,000
Economic interest (as a percent)																	90.50%																				81.43%
Ownership percentage before acquiring additional interest																	79.00%
Area of land contributed to the joint venture (in acres)																																			4.8
Value of the land contributed to joint venture																																			15,500,000
Cash contributed by joint venture partner																																			3,000,000
Construction loan secured																																			37,700,000
Share of distributable cash				1,130,000																																																			8,600,000
Secured debt																																																								9,100,000
Share of the entity in secured debt																																																								$ 2,500,000	$ 100,000	$ 1,400,000					$ 1,000,000