CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) (USD $) In Thousands, unless otherwise specified	Total	PREFERRED SHARES	COMMON SHARES, $0.01 PAR VALUE	Additional Paid-in Capital [Member]	RETAINED EARNINGS	Accumulated Other Comprehensive (Loss)	OPERATING PARTNERSHIP	Partially Owned Properties [Member]
Beginning Balance, Noncontrolling Interest at Dec. 31, 2013	$ 337,995						$ 211,412	$ 126,583
Beginning Balance, Parent at Dec. 31, 2013	10,507,201	50,000	3,605	8,561,500	2,047,258	(155,162)
Common Share Issuance:
Conversion of OP Units held by Noncontrolling Interests into OP Units held by General Partner			1	1,717			(1,718)
Exercise of share options			14	56,540
Stock Issued During Period, Value, Employee Stock Purchase Plan				2,728
Share-based employee compensation expense:
Adjustments to Additional Paid in Capital, Share-based Compensation, Restricted Stock Unit or Restricted Stock Award, Requisite Service Period Recognition			2	8,392
Share options				6,326
ESPP discount				701
Payments for Repurchase of Common Stock	(1,777)			(1,777)
Supplemental Executive Retirement Plan (SERP)				5,664
Acquisition Noncontrolling Interests Partially Owned Properties				(2,308)				(2,244)
Change in market value	(69,579)			(69,579)
Adjustment for Noncontrolling Interests ownership in Operating Partnership				4,272			(4,272)
Net income attributable to controlling interests	413,569				413,569
Common Share distributions					(542,374)
Dividends, Preferred Stock, Cash					(3,109)
Other comprehensive (loss) income – derivative instruments:
Unrealized holding (losses) arising during the period	(21,784)					(21,784)
Losses reclassified into earnings from other comprehensive income	(12,606)					12,606
Currency translation adjustments arising during the period	(466)					(466)
Issuance of LTIP Units to Noncontrolling Interests							3
Equity Compensation associated with Noncontrolling Interests							11,144
Net (Income) Attributable to Noncontrolling Interest	16,273						16,273	1,800
Contributions by Noncontrolling Interests	5,684							5,684
Distributions to Noncontrolling Interests							(21,527)	(6,795)
Change in carrying value							2,574
Stockholders' Equity, Other								169
Ending Balance, Noncontrolling Interest at Sep. 30, 2014	339,086						213,889	125,197
Ending Balance, Parent at Sep. 30, 2014	$ 10,378,336	$ 50,000	$ 3,622	$ 8,574,176	$ 1,915,344	$ (164,806)