Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Operating Activities
Net income	$ 182,243	$ 659,567
Adjustment to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	249,950	212,558
Depreciable real estate reserves, net of recoveries	(5,789)
Equity in net income from unconsolidated joint ventures	(80,988)	(7,663)
Equity in net gain on sale of interest in unconsolidated joint venture	(11,987)	(3,032)
Gain on sale of discontinued operations	(6,627)	(46,085)
Distributions of cumulative earnings from unconsolidated joint ventures	84,182	9,787
Preferred stock redemption costs	(10,010)
Purchase price fair value adjustment		(489,889)
Gain on sale of debt securities		(19,840)
Loan loss and other investment reserves, net of recoveries	564	(1,870)
(Gain) loss on sale of investments in marketable securities	(2,237)	133
Gain on early extinguishment of debt		(904)
Deferred rents receivable	(50,910)	(64,600)
Other non-cash adjustments	1,718	3,158
Changes in operating assets and liabilities:
Restricted cash - operations	(12,557)	1,757
Tenant and other receivables	(8,500)	(3,130)
Related party receivables	(3,792)	524
Deferred lease costs	(37,885)	(25,483)
Other assets	(44,915)	(11,994)
Accounts payable, accrued expenses and other liabilities	11,309	12,692
Deferred revenue and land leases payable	12,187	12,010
Net cash provided by operating activities	265,956	237,696
Investing Activities
Acquisitions of real estate property	(405,318)	(331,972)
Additions to land, buildings and improvements	(107,425)	(111,485)
Escrowed cash - capital improvements/acquisition deposits	(68,692)	39,886
Investments in unconsolidated joint ventures	(159,524)	(95,611)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	48,510	107,753
Net proceeds from disposition of real estate/joint venture interest	70,367	160,548
Other investments	(28,911)	(16,374)
Debt and preferred equity and other investments, net of repayments/participations	(178,183)	(254,264)
Net cash used in investing activities	(829,176)	(501,519)
Financing Activities
Proceeds from mortgages and other loans payable	1,113,500	740,000
Repayments of mortgages and other loans payable	(484,518)	(754,358)
Proceeds from revolving credit facility and senior unsecured notes	813,339	1,401,068
Repayments of revolving credit facility and senior unsecured notes	(1,065,793)	(1,393,144)
Proceeds from stock options exercised and DRIP issuance	112,447	8,278
Net proceeds from issuance of preferred/common stock	423,544	516,350
Redemption of preferred stock	(190,003)
Purchase of treasury stock	(11,197)	(4,313)
Distributions to noncontrolling interests in other partnerships	(15,622)	(143,474)
Contributions from noncontrolling interests in other partnerships	19,181
Distributions to noncontrolling interests in Operating Partnership	(2,385)	(572)
Dividends paid on common and preferred stock	(91,272)	(47,684)
Deferred loan costs and capitalized lease obligation	(33,830)	3,347
Net cash provided by financing activities	587,391	325,498
Net increase in cash and cash equivalents	24,171	61,675
Cash and cash equivalents at beginning of period	138,192	332,830
Cash and cash equivalents at end of period	$ 162,363	$ 394,505