CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Revenue:
Rental and other income	$ 309,859	$ 243,483
Management, development and other fees	2,272	2,549
Total revenue	312,131	246,032
Expenses:
Operating expenses, excluding property taxes	73,971	64,321
Property taxes	32,963	23,887
Interest expense, net	38,174	33,626
Loss on extinguishment of debt, net		1,179
Depreciation expense	109,829	61,571
General and administrative expense	10,039	9,710
Expensed acquisition, development and other pursuit costs	40,059	239
Total expenses	305,035	194,533
Equity in income (loss) of unconsolidated entities	(18,564)	2,175
Income (loss) from continuing operations	(11,468)	53,674
Discontinued operations:
Income from discontinued operations	2,446	3,935
Gain on sale of real estate assets	84,491
Total discontinued operations	86,937	3,935
Net income	75,469	57,609
Net loss (income) attributable to noncontrolling interests	(42)	149
Net income attributable to common stockholders	75,427	57,758
Other comprehensive income:
Unrealized gain on cash flow hedges		11,008
Cash flow hedge losses reclassified to earnings	1,391
Comprehensive income	$ 76,818	$ 68,766
Earnings per common share - basic:
Income (loss) from continuing operations attributable to common stockholders (in dollars per share)	$ (0.10)	$ 0.57
Discontinued operations attributable to common stockholders (in dollars per share)	$ 0.73	$ 0.04
Net income attributable to common stockholders (in dollars per share)	$ 0.63	$ 0.61
Earnings per common share - diluted:
Income (loss) from continuing operations attributable to common stockholders (in dollars per share)	$ (0.10)	$ 0.56
Discontinued operations attributable to common stockholders (in dollars per share)	$ 0.73	$ 0.04
Net income attributable to common stockholders (in dollars per share)	$ 0.63	$ 0.60
Dividends per common share (in dollars per share)	$ 1.07	$ 0.97