CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenue:
Rental and other income		$ 454,517	$ 411,134	$ 894,273	$ 808,131
Management, development and other fees		2,942	2,672	5,553	5,750
Total revenue		457,459	413,806	899,826	813,881
Expenses:
Operating expenses, excluding property taxes		112,069	101,059	224,845	199,601
Property taxes		45,913	42,439	93,089	86,924
Interest expense, net	[1]	44,590	43,722	90,164	86,255
Gains (Losses) on Extinguishment of Debt		(7,749)	412	(7,749)	412
Depreciation expense	[1]	118,627	110,395	235,480	216,762
General and administrative expense		11,628	10,220	22,111	19,456
Expensed Acquisition, Development And Other Pursuit Costs, Net of Recoveries		673	2,017	1,860	2,732
Casualty and Impairment (Gain) Loss		(17,114)	0	(11,326)	0
Total expenses		308,637	310,264	648,474	612,142
Equity in income of unconsolidated real estate entities		13,806	7,710	48,371	12,933
Gain on sale of real estate		9,625	0	9,647	0
Gain on sale of communities		0	60,945	70,936	60,945
Income (loss) from continuing operations		172,253	172,197	380,306	275,617
Discontinued operations:
Income from discontinued operations		0	0	0	310
Gain on sale of discontinued operations		0	0	0	37,869
Total discontinued operations		0	0	0	38,179
Net income		172,253	172,197	380,306	313,796
Net loss (income) attributable to noncontrolling interests		71	(14,111)	163	(13,971)
Net income attributable to common stockholders		172,324	158,086	380,469	299,825
Other comprehensive income:
Cash flow hedge losses reclassified to earnings		1,427	1,438	2,992	3,011
Comprehensive income		$ 173,751	$ 159,524	$ 383,461	$ 302,836
Earnings per common share - basic:
Income (loss) from continuing operations attributable to common stockholders (in dollars per share)		$ 1.30	$ 1.22	$ 2.88	$ 2.02
Discontinued operations attributable to common stockholders (in dollars per share)		0.00	0.00	0.00	0.29
Net income attributable to common stockholders (in dollars per share)		1.30	1.22	2.88	2.31
Earnings per common share - diluted:
Income (loss) from continuing operations attributable to common stockholders (in dollars per share)		1.29	1.21	2.86	2.02
Discontinued operations attributable to common stockholders (in dollars per share)		0.00	0.00	0.00	0.29
Net income attributable to common stockholders (in dollars per share)		1.29	1.21	2.86	2.31
Dividends per common share: (in dollars per share)		$ 1.25	$ 1.16	$ 2.50	$ 2.32

[1] Includes amounts associated with assets sold or held for sale, not classified as discontinued operations.