CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Comprehensive income (loss):
Net income	$ 581,753	$ 10,089	$ 714,819	$ 67,945
Other comprehensive (loss) - derivative instruments:
Unrealized holding (losses) arising during the period	(31,201)	(72,243)	(25,119)	(85,746)
Losses reclassified into earnings from other comprehensive income	935	739	1,891	1,465
Other comprehensive income (loss) - other instruments:
Unrealized holding gains (losses) arising during the period	347	93	493	(66)
Other comprehensive (loss)	(29,919)	(71,411)	(22,735)	(84,347)
Comprehensive income	551,834	(61,322)	692,084	(16,402)
Comprehensive (income) attributable to Noncontrolling Interests Partially Owned Properties	(25,829)	(128)	(31,564)	(2,501)
Comprehensive income (loss) attributable to controlling interests	$ 526,005	$ (61,450)	$ 660,520	$ (18,903)

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