MORTGAGES, NOTES AND LOANS PAYABLE (Details 2) (USD $)				9 Months Ended				1 Months Ended	9 Months Ended		0 Months Ended					3 Months Ended	9 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			1 Months Ended	9 Months Ended		1 Months Ended		1 Months Ended	9 Months Ended	0 Months Ended			3 Months Ended		9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Development Loan	Sep. 30, 2012 Development Loan Maximum	Sep. 30, 2012 Special Improvement District bonds	Dec. 31, 2011 Special Improvement District bonds	Dec. 31, 2011 SID Payable to Nevada Cancer Institute	May 31, 2011 110 N. Wacker	Sep. 30, 2012 110 N. Wacker	Dec. 31, 2011 110 N. Wacker	Aug. 15, 2012 70 Columbia Corporate Center	Sep. 30, 2012 70 Columbia Corporate Center	Sep. 30, 2012 Other Financing Arrangements	Dec. 31, 2011 Bridgeland	Sep. 30, 2012 Bridgeland Minimum	Sep. 30, 2012 Bridgeland Land Loan	Sep. 30, 2012 Bridgeland Land Loan	Sep. 30, 2012 Bridgeland Development Loan	Sep. 30, 2012 Bridgeland Development Loan	Dec. 31, 2011 Bridgeland Note # 1 - # 4	Sep. 30, 2012 Summerlin South S108	Dec. 31, 2011 Summerlin South S108	Sep. 30, 2012 Summerlin South S124	Dec. 31, 2011 Summerlin South S124	Sep. 30, 2012 Summerlin South S128	Dec. 31, 2011 Summerlin South S128	Sep. 30, 2012 Summerlin South S128C	Dec. 31, 2011 Summerlin South S128C	Sep. 30, 2012 Summerlin South S132	Dec. 31, 2011 Summerlin South S132	Sep. 30, 2012 Summerlin South S151	Dec. 31, 2011 Summerlin South S151	Sep. 30, 2012 Summerlin West S808	Dec. 31, 2011 Summerlin West S808	Sep. 30, 2012 Summerlin West S809	Dec. 31, 2011 Summerlin West S809	Sep. 30, 2012 Summerlin West S810	Dec. 31, 2011 Summerlin West S810	Sep. 30, 2012 The Shops at Summerlin Centre S108	Dec. 31, 2011 The Shops at Summerlin Centre S108	Sep. 30, 2012 The Shops at Summerlin Centre S128	Dec. 31, 2011 The Shops at Summerlin Centre S128	Sep. 30, 2012 The Woodlands	Dec. 31, 2011 The Woodlands	Sep. 30, 2012 The Woodlands TWL Facility	Sep. 30, 2012 The Woodlands TWL Facility	Dec. 31, 2011 The Woodlands TWL Facility	Sep. 30, 2012 The Woodlands TWL Facility Maximum	Sep. 30, 2012 The Woodlands TWL Facility March 29, 2013	Sep. 30, 2012 The Woodlands TWL Facility March 29, 2014	Sep. 30, 2012 The Woodlands TWL Facility June 29, 2014	Sep. 30, 2012 The Woodlands TWL Facility September 29, 2014	Sep. 30, 2012 The Woodlands TWL Facility December 29, 2014	Sep. 30, 2012 The Woodlands Term loan	Sep. 30, 2012 The Woodlands Revolving credit line	Sep. 30, 2012 The Woodlands Capital lease obligation	Dec. 31, 2011 The Woodlands Capital lease obligation	Sep. 30, 2012 Resort and Conference Center Room Acres	Sep. 30, 2012 Resort and Conference Center	Dec. 31, 2011 Resort and Conference Center	Sep. 30, 2012 2201 Lake Woodlands Drive	Dec. 31, 2011 2201 Lake Woodlands Drive	Sep. 30, 2012 Weiner Tract	Dec. 31, 2011 Weiner Tract	Sep. 30, 2012 Land in Montgomery Co.	Dec. 31, 2011 Land in Montgomery Co.	Sep. 30, 2012 Land in Harris Co.	Dec. 31, 2011 Land in Harris Co.	Sep. 30, 2012 CVS	Dec. 31, 2011 CVS	Dec. 31, 2011 4 Waterway	Sep. 30, 2012 4 Waterway	Dec. 31, 2011 9303 New Trails	Sep. 30, 2012 9303 New Trails	Dec. 05, 2011 4 Waterway and 9303 New Trails	Feb. 29, 2012 3 Waterway Square	Sep. 30, 2012 3 Waterway Square item	Feb. 02, 2012 3 Waterway Square item sqft	Apr. 30, 2012 20/25 Waterway	Sep. 30, 2012 20/25 Waterway	May 31, 2012 Millennium Waterway Apartments	Sep. 30, 2012 Millennium Waterway Apartments	Sep. 17, 2012 Ward Centers	Sep. 30, 2012 Ward Centers	Dec. 31, 2011 Ward Centers	Sep. 30, 2012 Ward Centers Minimum	Sep. 30, 2012 Ward Centers Maximum	Sep. 30, 2012 Victoria Ward	Dec. 31, 2011 Victoria Ward
Mortgages, notes and loans payable
Interest rate (as a percent)							5.95%		5.21%	5.21%		4.25%				5.50%	5.50%	5.00%	5.00%	6.50%	5.95%	5.95%	5.95%	5.95%	7.30%	7.30%	6.05%	6.05%	6.00%	6.00%	6.00%	6.00%	5.71%	5.71%	6.65%	6.65%	7.13%	7.13%	5.95%	5.95%	6.05%	6.05%			5.00%	5.00%	5.00%									2.72%	2.72%	6.00%	6.00%	5.50%	5.25%	5.25%	6.25%	6.25%	6.00%	6.00%	6.00%	6.00%	3.25%	3.25%	4.88%	4.88%	4.88%	4.88%	4.88%		3.25%			4.79%		3.75%		3.40%					3.45%
Maximum Facility Amount			$ 140,000,000															$ 30,000,000	$ 30,000,000																										$ 270,000,000	$ 270,000,000								$ 170,000,000	$ 100,000,000																						$ 43,295,000							$ 250,000,000
Total mortgages, notes and loans payable	683,804,000	606,477,000			50,928,000	55,213,000	50,000		29,000,000	29,000,000		16,037,000	754,000	20,604,000		18,066,000	18,066,000	2,757,000	2,757,000	20,604,000	1,183,000	1,302,000	342,000	378,000	825,000	862,000	5,847,000	5,956,000	5,067,000	5,378,000	11,064,000	12,293,000		682,000		1,000,000	22,185,000	22,770,000	650,000	713,000	3,765,000	3,829,000	337,262,000	281,660,000	176,704,000	176,704,000	183,000,000									67,000	147,000	36,100,000	36,100,000	36,100,000		4,803,000		1,479,000		649,000		381,000		101,000	41,000,000	40,359,000	14,000,000	13,781,000			217,000			14,450,000		55,584,000		229,000,000	220,000,000
Variable rate basis				three-month LIBOR					one-month LIBOR								three-month LIBOR		LIBOR																											one-month LIBOR													one-month LIBOR																	LIBOR	one-month LIBOR											one-month LIBOR
Interest rate margin (as a percent)									2.25%							2.75%	2.75%	3.25%	3.25%																										4.00%	4.00%												5.00%	5.00%																		2.65%	2.65%										2.50%
Outstanding principal balance of debt that is swapped to fixed rate through maturity	172,000,000								29,000,000																																																																															143,000,000
Fixed interest rate per swap (as a percent)									5.21%																																																																															3.80%
Term of debt instrument																10 years		3 years																																																													10 years
Period for which interest rate is fixed																5 years
Period for which interest rate is floating																5 years
Fixed interest rate (as a percent)																5.50%	5.50%																																																															4.79%		3.75%
Interest rate (as a percent)																			5.00%
Maximum outstanding loan amount at any time																		30,000,000	30,000,000
Amount of borrowings								29,000,000			16,000,000																																																												41,000,000		14,000,000			43,300,000							9,000,000
Rate of LIBOR floor (as a percent)																																														1.00%													1.00%
Interest rate increase every six months until maturity (as a percent)																																																										50.00%	50.00%
Monthly principal and interest payment required																																																																																		257,418
Annual principal payments as a percentage of outstanding principal balance																5.00%	5.00%
Cash balance required to be maintained															3,000,000
Net worth required to be maintained															250,000,000
Period of real estate taxes and debt service required to be escrowed with the lender																	1 year
Non-recourse mortgage assumed																																																																																	55,600,000
Proceeds from the loan																																																																															13,600,000
Number of stories of building to be constructed with loan proceeds																																																																														11
Area of office building to be constructed using proceeds from loan																																																																														232,021
Number of extension options																																																																													2
Weighted average interest rate (as a percent)	4.52%	4.68%																																																																																		3.40%
Corporate recourse guarantee amount	7,000,000								7,000,000
Area of land securing debt (in acres)																																																										40
Extension period at borrower's option (in years)																																													1 year													1 year																			1 year
Percentage of loan to value ratio at which debt will not be amortized on dollar for dollar basis for distributions made from The Woodlands																																																40.00%
Leverage expressed as loan to value ratio (as a percent)																																													37.90%	37.90%
Undrawn and available borrowing capacity																																													11,000,000	11,000,000
Amount of future required repayments																																																	25,000,000	30,000,000	10,000,000	10,000,000	10,000,000
Number of rooms in property securing debt (in rooms)																																																										440
Loan to value ratio to draw additional loan proceeds (as a percent)																																																																																							65.00%
Percentage of debt yield to draw additional loan proceeds																																																																																						10.00%
Unused portion of the debt instrument																																																																																				21,000,000
Amount to which debt will amortize ratably through maturity following an interest-only period									12,000,000
Land, buildings and equipment and developments in progress pledged as collateral	$ 1,100,000,000