CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Investment in real estate
Land	$ 6,296,735	$ 6,192,512
Depreciable property	19,730,737	19,226,047
Projects under development	1,006,992	988,867
Land held for development	306,625	393,522
Real Estate Investment Property, at Cost	27,341,089	26,800,948
Real Estate Investment Property, Accumulated Depreciation	(5,170,438)	(4,807,709)
Investment in real estate, net	22,170,651	21,993,239
Cash and cash equivalents	76,132	53,534
Investments in unconsolidated entities	142,318	178,526
Deposits - restricted	84,408	103,567
Escrow deposits - mortgage	45,269	42,636
Deferred financing costs, net	63,441	58,486
Other assets	409,183	404,557
Total assets	22,991,402	22,834,545
Liabilities:
Mortgage notes payable	5,158,091	5,174,166
Notes, net	5,923,952	5,477,088
Lines of credit	0	115,000
Accounts payable and accrued expenses	168,225	118,791
Accrued interest payable	78,389	78,309
Other liabilities	331,662	347,748
Security deposits	74,508	71,592
Distributions payable	187,906	243,511
Total liabilities	11,922,733	11,626,205
Commitments and contingencies
Redeemable Noncontrolling Interests - Operating Partnership	440,050	363,144
Shareholders' equity:
Preferred Shares of beneficial interest, $0.01 par value; 100,000,000 shares authorized; 1,000,000 shares issued and outstanding as of June 30, 2014 and December 31, 2013	50,000	50,000
Common Shares of beneficial interest, $0.01 par value; 1,000,000,000 shares authorized; 361,562,007 shares issued and outstanding as of June 30, 2014 and 360,479,260 shares issued and outstanding as of December 31, 2013	3,616	3,605
Paid in capital	8,527,380	8,561,500
Retained earnings	1,875,732	2,047,258
Accumulated other comprehensive (loss)	(166,990)	(155,162)
Total shareholders' equity	10,289,738	10,507,201
Noncontrolling Interests:
Operating Partnership	213,038	211,412
Noncontrolling Interests - Partially Owned Properties	125,843	126,583
Total Noncontrolling Interests	338,881	337,995
Total equity	10,628,619	10,845,196
Total liabilities and equity	$ 22,991,402	$ 22,834,545