DISPOSITIONS, DISCONTINUED OPERATIONS AND GAINS (LOSSES) ON DISPOSITIONS OF INTERESTS IN OPERATING PROPERTIES (Details) (USD $)	3 Months Ended
	Mar. 31, 2013 property sqft	Mar. 31, 2012
Discontinued operations
Number of properties sold	2
Area of real estate property sold	2,000,000
Debt on the property paid down with proceeds from sale	$ 121,200,000
Total revenues	637,803,000	596,613,000
Total expenses	437,442,000	430,697,000
Operating income	200,361,000	165,916,000
Gain on extinguishment of debt	(9,319,000)
Discontinued operations, net	18,927,000	(11,509,000)
Discontinuing operations
Discontinued operations
Retail and other revenue	1,067,000	36,238,000
Total revenues	1,067,000	36,238,000
Retail and other operating expenses	1,214,000	27,701,000
Provisions for impairment and other gains	4,975,000	10,393,000
Total expenses	6,189,000	38,094,000
Operating income	(5,122,000)	(1,856,000)
Interest expense, net	(1,521,000)	(9,609,000)
Gain on extinguishment of debt	25,894,000
Net (loss) income from operations	19,251,000	(11,465,000)
Provision for income taxes		(16,000)
Losses on dispositions	(324,000)	(28,000)
Discontinued operations, net	18,927,000	(11,509,000)
Discontinuing operations | Regional Malls sold through lender directed sale
Discontinued operations
Number of properties sold	1
Gain on extinguishment of debt	$ 25,900,000