Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues
Revenues from rental properties	$ 290,919	$ 279,286	$ 873,153	$ 859,492
Management and other fee income	3,926	5,790	12,456	14,274
Total revenues	294,845	285,076	885,609	873,766
Operating expenses
Rent	2,764	2,728	8,312	8,274
Real estate taxes	38,363	37,703	115,379	107,966
Operating and maintenance	33,197	32,590	102,862	100,366
General and administrative	28,588	27,983	86,395	89,840
Provision for doubtful accounts	701	1,092	4,201	5,752
Impairment charges			34,280	68,126
Depreciation and amortization	88,443	96,827	275,787	264,436
Total operating expenses	195,000	208,996	627,216	644,760
Operating income	99,845	76,080	258,393	229,006
Other income/(expense)
Other income, net	1,101	4,358	3,813	3,176
Interest expense	(47,258)	(46,552)	(139,830)	(149,482)
Early extinguishment of debt charges	(1,753)	(45,674)	(1,753)	(45,674)
Income/(loss) from continuing operations before income taxes, net, equity in income of joint ventures, net, gain on change in control of interests and equity in income from other real estate investments, net	51,935	(11,788)	120,623	37,026
Benefit/(provision) for income taxes, net	697	(61,426)	2,224	(73,292)
Equity in income of joint ventures, net	9,100	11,500	37,044	190,155
Gain on change in control of interests		6,584	71,160	53,096
Income/(loss) from continuing operations	81,683	(51,319)	293,003	229,517
Gain on sale of operating properties, net of tax	40,533	9,771	62,102	75,935
Net income/(loss)	122,216	(41,548)	355,105	305,452
Net income attributable to noncontrolling interests	(1,186)	(1,997)	(13,926)	(4,875)
Net income/(loss) attributable to the Company	121,030	(43,545)	341,179	300,577
Preferred stock redemption charge	(7,014)		(7,014)
Preferred stock dividends	(12,059)	(11,555)	(35,169)	(34,665)
Net income/(loss) available to the Company's common shareholders	$ 101,957	$ (55,100)	$ 298,996	$ 265,912
Net income/(loss) available to the Company:
-Basic (in dollars per share)	$ 0.24	$ (0.13)	$ 0.70	$ 0.63
-Diluted (in dollars per share)	$ 0.24	$ (0.13)	$ 0.70	$ 0.63
Weighted average shares:
-Basic (in shares)	423,688	420,073	423,574	416,829
-Diluted (in shares)	424,311	420,073	424,193	418,234
Joint Ventures [Member]
Other income/(expense)
Equity in income of joint ventures, net	$ 9,142	$ 11,537	$ 37,044	$ 190,155
Other Real Estate Investments [Member]
Other income/(expense)
Equity in income of joint ventures, net	19,909	3,774	61,952	22,532
Continuing Operations [Member]
Operating expenses
Impairment charges	$ 2,944	$ 10,073	$ 34,280	$ 68,126