Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
CASH FLOWS FROM OPERATING ACTIVITIES:
Consolidated Net Income	$ 401,103	$ 334,468
Adjustments to reconcile consolidated net income to net cash provided by operating activities -
Depreciation and amortization	330,562	321,974
Gain upon acquisition of controlling interests and sale or disposal of assets and interests in unconsolidated entities, net	(2,897)	(20,767)
Straight-line rent	(11,779)	(10,596)
Equity in income of unconsolidated entities	(57,423)	(54,231)
Distributions of income from unconsolidated entities	51,636	43,247
Changes in assets and liabilities -
Tenant receivables and accrued revenue, net	63,058	77,923
Deferred costs and other assets	(12,005)	(22,212)
Accounts payable, accrued expenses, intangibles, deferred revenues and other liabilities	(100,804)	(119,293)
Net cash provided by operating activities	661,451	550,513
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisitions	(85,459)	(51,564)
Funding of loans to related parties	(13,367)	(18,399)
Capital expenditures, net	(207,655)	(199,906)
Cash impact from the consolidation of properties	5,402
Net proceeds from sale of assets		73,209
Investments in unconsolidated entities	(45,861)	(15,669)
Purchase of marketable and non-marketable securities	(5,211)
Proceeds from sale of marketable and non-marketable securities		1,376
Distributions of capital from unconsolidated entities	124,676	198,726
Net cash used in investing activities	(227,475)	(12,227)
CASH FLOWS FROM FINANCING ACTIVITIES:
Issuance of units	(82)	121
Purchase of noncontrolling interest in consolidated properties	(89,818)
Distributions to noncontrolling interest holders in properties	(12,751)	(2,046)
Partnership distributions	(455,281)	(417,619)
Mortgage and unsecured indebtedness proceeds, net of transaction costs	1,810,496	642,698
Mortgage and unsecured indebtedness principal payments	(2,390,035)	(1,115,992)
Net cash used in financing activities	(1,137,471)	(892,838)
DECREASE IN CASH AND CASH EQUIVALENTS	(703,495)	(354,552)
CASH AND CASH EQUIVALENTS, beginning of period	1,716,863	1,184,518
CASH AND CASH EQUIVALENTS, end of period	$ 1,013,368	$ 829,966