Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Operating Activities
Net income	$ 153,614	$ 643,078
Adjustment to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	162,028	136,355
Depreciable real estate reserves, net of recoveries	(5,789)
Equity in net income from unconsolidated joint ventures	(69,330)	(10,390)
Equity in net gain on sale of interest in unconsolidated joint venture	(16,794)
Gain on sale of discontinued operations	(6,627)	(46,085)
Distributions of cumulative earnings from unconsolidated joint ventures	77,981	7,866
Purchase price fair value adjustment		(488,890)
Gain on sale of debt securities		(19,840)
Loan loss and other investment reserves, net of recoveries	564	(1,870)
Loss on investments in marketable securities		133
Gain on early extinguishment of debt		(971)
Deferred rents receivable	(37,318)	(44,343)
Other non-cash adjustments	3,759	3,774
Changes in operating assets and liabilities:
Restricted cash - operations	(7,104)	15,487
Tenant and other receivables	(5,006)	(841)
Related party receivables	(3,792)	1,157
Deferred lease costs	(28,549)	(14,534)
Other assets	(27,176)	5,169
Accounts payable, accrued expenses and other liabilities	9,609	(5,323)
Deferred revenue and land leases payable	(2,135)	(3,084)
Net cash provided by operating activities	197,935	176,848
Investing Activities
Acquisitions of real estate property	(248,468)	(331,972)
Additions to land, buildings and improvements	(76,585)	(57,442)
Escrowed cash - capital improvements/acquisition deposits	(65,030)	46,861
Investments in unconsolidated joint ventures	(131,820)	(60,321)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	44,172	102,089
Net proceeds from disposition of real estate/joint venture interest	26,099	150,893
Other investments	(31,206)	631
Debt and preferred equity and other investments, net of repayments/participations	(75,209)	84,528
Net cash used in investing activities	(558,047)	(64,733)
Financing Activities
Proceeds from mortgages and other loans payable	1,113,500	690,000
Repayments of mortgages and other loans payable	(472,288)	(744,873)
Proceeds from revolving credit facility and senior unsecured notes	468,339	725,079
Repayments of revolving credit facility and senior unsecured notes	(840,793)	(962,395)
Proceeds from stock options exercised and DRIP issuance	105,195	7,097
Net proceeds from sale of common stock	201,307	419,463
Purchase of treasury stock	(11,158)	(4,197)
Distributions to noncontrolling interests in other partnerships	(11,999)	(133,712)
Contributions from noncontrolling interests in other partnerships	18,799
Distributions to noncontrolling interests in Operating Partnership	(1,561)	(382)
Dividends paid on common and preferred stock	(59,155)	(31,662)
Deferred loan costs and capitalized lease obligation	(31,467)	(19,134)
Net cash provided by (used in) financing activities	478,719	(54,716)
Net increase in cash and cash equivalents	118,607	57,399
Cash and cash equivalents at beginning of period	138,192	332,830
Cash and cash equivalents at end of period	$ 256,799	$ 390,229