MORTGAGES, NOTES AND LOANS PAYABLE (Details 2) (USD $)	12 Months Ended							0 Months Ended	12 Months Ended		0 Months Ended		12 Months Ended						12 Months Ended																											12 Months Ended												0 Months Ended	12 Months Ended												0 Months Ended		0 Months Ended		0 Months Ended	12 Months Ended		0 Months Ended			12 Months Ended		0 Months Ended	9 Months Ended			12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012 Development Loan	Dec. 31, 2012 Special Improvement District bonds	Dec. 31, 2011 Special Improvement District bonds	Dec. 31, 2012 SID Payable to Nevada Cancer Institute	Dec. 31, 2011 SID Payable to Nevada Cancer Institute	May 31, 2012 110 N. Wacker	Dec. 31, 2012 110 N. Wacker	Dec. 31, 2011 110 N. Wacker	Aug. 15, 2012 70 Columbia Corporate Center	Dec. 31, 2012 70 Columbia Corporate Center	Dec. 31, 2012 Hughes Landing	Nov. 14, 2012 Hughes Landing acre	Dec. 31, 2012 Other Financing Arrangements	Dec. 31, 2012 Bridgeland acre	Dec. 31, 2011 Bridgeland	Dec. 31, 2012 Bridgeland Minimum	Dec. 31, 2012 Bridgeland Land Loan	Dec. 31, 2012 Bridgeland Development Loan	Dec. 31, 2011 Bridgeland Note # 1 - # 4	Dec. 31, 2012 Summerlin South S108	Dec. 31, 2011 Summerlin South S108	Dec. 31, 2012 Summerlin South S124	Dec. 31, 2011 Summerlin South S124	Dec. 31, 2012 Summerlin South S128	Dec. 31, 2011 Summerlin South S128	Dec. 31, 2012 Summerlin South S128C	Dec. 31, 2011 Summerlin South S128C	Dec. 31, 2012 Summerlin South S132	Dec. 31, 2011 Summerlin South S132	Dec. 31, 2012 Summerlin South S151	Dec. 31, 2011 Summerlin South S151	Dec. 31, 2012 Summerlin South S808	Dec. 31, 2011 Summerlin South S808	Dec. 31, 2012 Summerlin South S809	Dec. 31, 2011 Summerlin South S809	Dec. 31, 2012 Summerlin South S810	Dec. 31, 2011 Summerlin South S810	Dec. 31, 2012 The Shops at Summerlin Centre S108	Dec. 31, 2011 The Shops at Summerlin Centre S108	Dec. 31, 2012 The Shops at Summerlin Centre S128	Dec. 31, 2011 The Shops at Summerlin Centre S128	Dec. 31, 2012 The Woodlands	Dec. 31, 2011 The Woodlands	Dec. 31, 2012 The Woodlands TWL Facility	Dec. 31, 2011 The Woodlands TWL Facility	Dec. 31, 2012 The Woodlands TWL Facility Maximum	Dec. 31, 2012 The Woodlands TWL Facility March 29, 2013	Dec. 31, 2012 The Woodlands TWL Facility March 29, 2014	Dec. 31, 2012 The Woodlands TWL Facility June 29, 2014	Dec. 31, 2012 The Woodlands TWL Facility September 29, 2014	Dec. 31, 2012 The Woodlands TWL Facility December 29, 2014	Dec. 31, 2012 The Woodlands Term loan	Dec. 31, 2012 The Woodlands Revolving credit line	Dec. 31, 2012 The Woodlands Capital lease obligation	Dec. 31, 2011 The Woodlands Capital lease obligation	Feb. 08, 2013 Resort and Conference Center	Dec. 31, 2012 Resort and Conference Center item acre	Dec. 31, 2011 Resort and Conference Center	Dec. 31, 2012 2201 Lake Woodlands Drive	Dec. 31, 2011 2201 Lake Woodlands Drive	Dec. 31, 2012 Weiner Tract	Dec. 31, 2011 Weiner Tract	Dec. 31, 2012 Land in Montgomery Co.	Dec. 31, 2011 Land in Montgomery Co.	Dec. 31, 2012 Land in Harris Co.	Dec. 31, 2011 Land in Harris Co.	Dec. 31, 2012 CVS	Dec. 31, 2011 CVS	Dec. 31, 2011 4 Waterway	Dec. 31, 2012 4 Waterway	Dec. 31, 2011 9303 New Trails	Dec. 31, 2012 9303 New Trails	Feb. 29, 2012 3 Waterway Square	Dec. 31, 2012 3 Waterway Square item	Feb. 02, 2012 3 Waterway Square sqft item	Apr. 30, 2012 20/25 Waterway	Dec. 31, 2012 20/25 Waterway	Dec. 31, 2011 20/25 Waterway	Dec. 31, 2012 Millennium Waterway Apartments	May 31, 2012 Millennium Waterway Apartments	Sep. 17, 2012 Ward Centers	Sep. 30, 2011 Ward Centers item	Dec. 31, 2012 Ward Centers	Dec. 31, 2011 Ward Centers	Dec. 31, 2012 Ward Centers Minimum	Dec. 31, 2012 Ward Centers Maximum
Mortgages, notes and loans payable
Interest rate (as a percent)									5.21%	5.21%		4.25%	2.86%						5.50%	5.00%		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%									2.84%	2.84%		6.00%	6.00%	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%		2.86%			4.79%	4.79%	3.75%				3.39%
Proceeds from non-recourse construction financing to redevelop the property																																																											$ 95,000,000
Maximum Facility Amount			140,000,000										38,000,000							30,000,000																										270,000,000								170,000,000	100,000,000																					43,295,000								250,000,000	250,000,000
Total mortgages, notes and loans payable	688,312,000	606,477,000		49,712,000	55,213,000		50,000		29,000,000	29,000,000		16,037,000	10,000		612,000	18,066,000	20,604,000		18,066,000		20,604,000	1,067,000	1,302,000	324,000	378,000	787,000	862,000	5,739,000	5,956,000	4,822,000	5,378,000	10,501,000	12,293,000		682,000		1,000,000	22,185,000	22,770,000	586,000	713,000	3,701,000	3,829,000	345,885,000	281,660,000	176,704,000	183,000,000									41,000	147,000	95,000,000	36,100,000	36,100,000		4,803,000		1,479,000		649,000		381,000		101,000	41,000,000	40,140,000	14,000,000	13,706,000		9,150,000			14,450,000		55,584,000	55,600,000			229,000,000	220,000,000
Variable rate basis									one-month LIBOR				LIBOR						three-month LIBOR	LIBOR																																																							LIBOR	one-month LIBOR								one-month LIBOR
Interest rate margin (as a percent)									2.25%					2.65%					2.75%	3.25%																										4.00%																													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%																																																											4.79%	4.79%		3.75%
Interest rate (as a percent)																				5.00%
Amount of borrowings								29,000,000			16,000,000																																																												41,000,000		14,000,000		43,300,000								9,000,000
Monthly principal and interest payment required																																																																																	257,418
Annual principal payments as a percentage of outstanding principal balance																			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
Proceeds from the loan																																																																														13,600,000						212,500,000
Repayments of mortgage debt from loan proceeds	36,100,000								28,200,000																																																																											208,700,000
Number of secured mortgages repaid																																																																																				3
Pre-tax loss on early repayment of debt		(11,305,000)																																																																																		11,300,000
Number of stories of building to be constructed with loan proceeds																																																																													11
Area of office building to be constructed using proceeds from loan																																																																													232,000
Number of extension options																																																											3																	2
Weighted average interest rate (as a percent)	4.49%	4.68%				5.95%	5.95%																																																																														3.39%
Corporate recourse guarantee amount	7,000,000								7,000,000
Area of site (in acres)														200		7,182
Area of land securing debt (in acres)																																																											40
Extension period at borrower's option																																														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)																																														28.30%
Undrawn and available borrowing capacity																																														7,200,000
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
Option to extend, term																																																											1 year
Amount of loan repaid from proceeds of a non-recourse construction financing to redevelop the property																																																										95,000,000
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	$ 1,500,000,000