CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Investment in real estate
Land	$ 4,609,337	$ 4,367,816
Depreciable property	15,943,139	15,554,740
Projects under development	194,254	160,190
Land held for development	404,846	325,200
Investment in real estate	21,151,576	20,407,946
Accumulated depreciation	(4,880,808)	(4,539,583)
Investment in real estate, net	16,270,768	15,868,363
Cash and cash equivalents	45,623	383,921
Investments in unconsolidated entities	17,906	12,327
Deposits - restricted	120,440	152,237
Escrow deposits - mortgage	10,462	10,692
Deferred financing costs, net	38,823	44,608
Other assets	164,523	187,155
Total assets	16,668,545	16,659,303
Liabilities:
Mortgage notes payable	3,948,115	4,111,487
Notes, net	5,354,038	5,609,574
Lines of credit	7,000	0
Accounts payable and accrued expenses	105,602	35,206
Accrued interest payable	78,869	88,121
Other liabilities	370,046	291,289
Security deposits	68,758	65,286
Distributions payable	108,048	179,079
Total liabilities	10,040,476	10,380,042
Commitments and contingencies
Redeemable Noncontrolling Interests - Operating Partnership	414,219	416,404
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 September 30, 2012 and 1,600,000 shares issued and outstanding as of December 31, 2011	50,000	200,000
Common Shares of beneficial interest, $0.01 par value; 1,000,000,000 shares authorized; 302,674,716 shares issued and outstanding as of June 30, 2012 and 297,508,185 shares issued and outstanding as of December 31, 2011	3,027	2,975
Paid in capital	5,364,802	5,047,186
Retained earnings	770,697	615,572
Accumulated other comprehensive (loss)	(197,754)	(196,718)
Total shareholders' equity	5,990,772	5,669,015
Noncontrolling Interests:
Operating Partnership	147,650	119,536
Noncontrolling Interests - Partially Owned Properties	75,428	74,306
Total Noncontrolling Interests	223,078	193,842
Total equity	6,213,850	5,862,857
Total liabilities and equity	$ 16,668,545	$ 16,659,303