Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Cash Flows from Operating Activities:
Net Income	$ 22,638		$ 17,188
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	38,850		38,749
Amortization of deferred financing costs and debt discount	264		694
Impairment loss	10,023		1,225
Equity in earnings of real estate joint ventures and partnerships, net	(4,075)		(3,397)
Gain on sale of property	(4,074)		(1,060)
Gain on sale of real estate joint venture and partnership interests	(5,562)
Distributions of income from real estate joint ventures and partnerships, net	601		385
Changes in accrued rent and accounts receivable, net	16,703		19,961
Changes in other assets, net	(5,503)		(4,389)
Changes in accounts payable, accrued expenses and other liabilities, net	(27,524)		(44,167)
Other, net	2,771		2,844
Net cash provided by operating activities	45,112		28,033
Cash Flows from Investing Activities:
Acquisition of real estate and land	(20,135)		(18,881)
Development and capital improvements	(18,633)		(15,391)
Proceeds from sale of property and real estate equity investments, net	13,629		2,573
Change in restricted deposits and mortgage escrows	1,106		(10,746)
Notes receivable from real estate joint ventures and partnerships and other receivables:
Advances	(79)		(1,821)
Collections	59,897		2,041
Real estate joint ventures and partnerships:
Investments	(5,518)		(93)
Distributions of capital	3,347		4,141
Net cash provided by (used in) investing activities	33,614		(38,177)
Cash Flows from Financing Activities:
Proceeds from the issuance of common shares of beneficial interest, net	458		1,510
Principal payments of debt	(31,204)		(5,098)
Changes in unsecured revolving credit facilities	3,500		63,000
Common and preferred dividends paid	(43,333)		(41,391)
Debt issuance costs paid	(70)		(97)
Distributions to noncontrolling interests	(3,756)		(4,438)
Contributions from noncontrolling interests			1,600
Other, net	61		(27)
Net cash (used in) provided by financing activities	(74,344)		15,059
Net increase in cash and cash equivalents	4,382		4,915
Cash and cash equivalents at January 1	13,642	[1]	23,859
Cash and cash equivalents at March 31	18,024	[1]	28,774
Interest paid during the period (net of amount capitalized of $783 and $337, respectively)	40,836		48,360
Income taxes paid during the period			$ 177

[1] Consolidated Variable Interest Entities' Assets and Liabilities included in the above balances (See Note 17):