Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Operating Activities
Consolidated net loss	$ (13,747)	$ (52,666)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	177,305	148,464
Net gain on sale of marketable securities	(3,123)
Net gain on the sale of depreciable property	(44,699)	(156)
Other debt charges	4,059	1,030
Write off of bad debt	1,241	1,208
Loss from unconsolidated entities	2,680	1,922
Amortization of deferred financing costs and other	4,238	3,939
Amortization of deferred compensation	5,105	6,008
Amortization of convertible debt discount	719	1,895
Changes in income tax accruals	988	(292)
Changes in operating assets and liabilities:
(Increase)/decrease in operating assets	(10,642)	2,973
Decrease in operating liabilities	(9,049)	(12,546)
Net cash provided by operating activities	115,075	101,779
Investing Activities
Proceeds from sales of real estate investments, net	29,363
Proceeds from sale of marketable securities	3,497
Payments related to the buyout of joint venture partner		(16,141)
Acquisition of real estate assets (net of liabilities assumed) and initial capital expenditures	(109,148)
Cash paid in nonmonetary asset exchange	(28,124)
Development of real estate assets	(44,547)	(61,771)
Capital expenditures and other major improvements - real estate assets, net of escrow reimbursement	(37,691)	(36,432)
Capital expenditures - non-real estate assets	(2,477)	(2,645)
Investment in unconsolidated joint ventures	(33,245)	(5,681)
Distributions received from unconsolidated joint venture	488	479
Purchase deposits on pending real estate acquisitions	(44,176)
Net cash used in investing activities	(266,060)	(122,191)
Financing Activities
Payments on secured debt	(204,896)	(83,845)
Proceeds from the issuance of secured debt	19,204	51,880
Proceeds from the issuance of unsecured debt	296,964	149,190
Payments on unsecured debt	(167,790)	(79,488)
Net proceeds/(repayment) of revolving bank debt	(26,750)	(55,400)
Payment of financing costs	(3,380)	(2,491)
Issuance of common and restricted stock, net	3,832	4,376
Proceeds from the issuance of common shares through public offering, net	325,106	103,444
Payments for the repurchase of Series G preferred stock, net	(3,597)	(637)
Distributions paid to non-controlling interests	(2,952)	(2,685)
Distributions paid to preferred stockholders	(4,696)	(4,751)
Distributions paid to common stockholders	(67,912)	(57,092)
Net cash provided by financing activities	163,133	22,501
Net increase in cash and cash equivalents	12,148	2,089
Cash and cash equivalents, beginning of period	9,486	5,985
Cash and cash equivalents, end of period	21,634	8,074
Supplemental Information:
Interest paid during the period, net of amounts capitalized	83,233	78,991
Non-cash transactions:
Properties acquired, including intengibles in asset exchange	268,853
Properties disposed in asset exchange, net of accumulated depreciation	192,576
OP Units issued in partial consideration for property acquisition	62,878
Secured debt assumed in the acquisitions of properties, including asset exchange	247,805
Secured debt transferred in asset exchange	55,356
Fair market value adjustment of secured debt assumed in acquisitions of properties, including asset exchange	21,915
Issuance of restricted stock awards	6	16
Conversion of operating partnership non-controlling interests to common stock (1,894 shares in 2011 and 39,638 shares in 2010)	48	551
Retirement of fully depreciated assets		$ 7,183