Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
ASSETS
Accounts receivable, allowance for doubtful accounts	$ 38,351	$ 43,241
Receivable arising from the straight-lining of rents, allowance	4,448	3,290
Deferred leasing and financing costs, amortization	220,846	237,766
Identified intangible assets: Accumulated amortization	$ 362,516	$ 347,039
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS AND EQUITY
Preferred shares of beneficial interest: authorized shares	110,000,000	110,000,000
Preferred shares of beneficial interest: issued shares	51,184,609	42,186,709
Preferred shares of beneficial interest: outstanding shares	51,184,609	42,186,709
Common shares of beneficial interest: par value per share	$ 0.04	$ 0.04
Common shares of beneficial interest: authorized shares	250,000,000	250,000,000
Common shares of beneficial interest: issued shares	186,143,105	185,080,020
Common shares of beneficial interest: outstanding shares	186,143,105	185,080,020
Common Class A [Member]
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS AND EQUITY
Redeemable noncontrolling interests units outstanding	11,714,978	12,160,771
Cumulative Redeemable Preferred Unit [Member]
LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS AND EQUITY
Redeemable noncontrolling interests units outstanding	1,800,001	9,000,001