CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Net cash provided by operating activities:	$ 43,798	$ 39,394
Cash flows from investing activities:
Investment in real estate, including intangible assets	(29,172)	(14,162)
Net proceeds from sale of properties	2,357	74,508
Principal payments received on loans receivable	1,444	2,569
Investment in loans receivable	0	(558)
Increase in deferred leasing costs	(2,644)	(3,827)
Change in escrow deposits and restricted cash	5,006	(4,579)
Real estate deposits	(225)	(246)
Net cash used in investing activities	(23,234)	53,705
Cash flows from financing activities:
Dividends to common and preferred shareholders	(25,244)	(23,071)
Repurchase of exchangeable notes	(62,150)	0
Principal amortization payments	(15,049)	(15,130)
Principal payments on debt, excluding normal amortization	(115,712)	(27,498)
Change in revolving credit facility borrowing, net	20,000	0
Proceeds from term loan	161,000	0
Increase in deferred financing costs	(4,091)	(3,930)
Proceeds of mortgages and notes payable	6,500	0
Cash distributions to noncontrolling interests	(1,218)	(1,522)
Contributions from noncontrolling interests	889	0
Repurchase of preferred shares	(1,461)	(657)
Receipts on forward equity commitment, net	0	428
Exercise of employee common share options	0	495
Issuance of common shares, net	2,145	2,070
Net cash used in financing activities	(34,391)	(68,815)
Change in cash and cash equivalents	(13,827)	24,284
Cash and cash equivalents, at beginning of period	63,711	52,644
Cash and cash equivalents, at end of period	$ 49,884	$ 76,928