UNCONSOLIDATED REAL ESTATE AFFILIATES (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2012	Dec. 31, 2011
Assets:
Land	$ 4,260,197	$ 4,278,471
Buildings and equipment	18,765,489	18,806,858
Less accumulated depreciation	(1,524,105)	(1,440,301)
Construction in progress	311,216	376,529
Net property and equipment	21,812,797	22,021,557
Net investment in real estate	24,683,274	24,887,428
Cash and cash equivalents	564,808	624,815	494,772	572,872
Accounts and notes receivable, net	252,624	260,860
Deferred expenses, net	185,176	179,837
Prepaid expenses and other assets	1,249,638	1,329,465
Total assets	26,935,520	27,282,405
Liabilities and Owners' Equity:
Total liabilities and equity	26,935,520	27,282,405
Investment In and Loans To/From Unconsolidated Real Estate Affiliates, Net:
Owners' equity	8,751,584	7,705,020	8,342,546	8,579,345
Investment in and loans to/from Unconsolidated Real Estate Affiliates, Net	2,870,477	2,865,871
Reconciliation - Investment In and Loans To/From Unconsolidated Real Estate Affiliates:
Investment in and loans to/from Unconsolidated Real Estate Affiliates, Net	2,870,477	2,865,871
Unconsolidated
Assets:
Land	1,012,137	960,335
Buildings and equipment	8,297,631	7,658,965
Less accumulated depreciation	(2,149,603)	(2,080,361)
Construction in progress	193,139	173,419
Net property and equipment	7,353,304	6,712,358
Investment in unconsolidated joint ventures	711,200	1,201,044
Net investment in real estate	8,064,504	7,913,402
Cash and cash equivalents	363,581	485,387
Accounts and notes receivable, net	153,056	167,548
Deferred expenses, net	239,742	298,050
Prepaid expenses and other assets	149,610	140,229
Total assets	8,970,493	9,004,616
Liabilities and Owners' Equity:
Mortgages, notes and loans payable	6,557,943	6,463,377
Accounts payable, accrued expenses and other liabilities	411,219	509,064
Cumulative effect of foreign currency translation ("CFCT")	(122,779)	(158,195)
Owners' equity, excluding CFCT	2,124,110	2,190,370
Total liabilities and equity	8,970,493	9,004,616
Investment In and Loans To/From Unconsolidated Real Estate Affiliates, Net:
Owners' equity	2,001,331	2,032,175
Less: joint venture partners' equity	(1,130,393)	(1,105,457)
Plus: excess investment/basis differences	1,984,100	1,939,153
Investment in and loans to/from Unconsolidated Real Estate Affiliates, Net	2,855,038	2,865,871
Reconciliation - Investment In and Loans To/From Unconsolidated Real Estate Affiliates:
Asset - Investment in and loans to/from Unconsolidated Real Estate Affiliates	2,870,477	2,865,871
Liability - Investment in and loans to/from Unconsolidated Real Estate Affiliates	(15,439)
Investment in and loans to/from Unconsolidated Real Estate Affiliates, Net	$ 2,855,038	$ 2,865,871