Consolidated Statement Of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital	Accumulated Other Comprehensive (Loss) Income	Distributions in Excess of Accumulated Earnings	Noncontrolling Interests	Stockholders' Equity, Total [Member]	Series A Preferred Stock
Balance at Dec. 31, 2013		$ 361	$ 1,141,590	$ (366)	$ (773,301)	$ 15,223	$ 383,541	$ 34
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercise of options, net			127				127
Net Proceeds (in Millions)		125	594,940			(2,638)	592,427
Conversion of Series A-4 preferred stock	$ 0
Issuance and associated costs of Series A Preferred Stock						100	100
Share-based compensation - amortization and forfeitures			4,706		173		4,879
Net income	33,196				31,444	1,782	33,226
Unrealized gain on interest rate swaps	97			366		(269)	97
Distributions					(121,861)	(8,567)	130,428
Issuance of common OP units						24,064	24,064
Settlement of membership interest			(209)			(4)	(213)
Balance at Dec. 31, 2014		486	1,741,154	0	(863,545)	29,691	907,820	34
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercise of options, net			95				95
Net Proceeds (in Millions)		98	564,260			52,921	617,279
Conversion of Series A-4 preferred stock	6,900		6,900				6,900
Share-based compensation - amortization and forfeitures			6,905		203		7,108
Net income	170,473				160,418	9,185	(169,603)
Unrealized gain on interest rate swaps	0
Distributions					(156,870)	(11,026)	(167,896)
Issuance of preferred OP units					(4,328)		(4,328)
Balance at Dec. 31, 2015	1,536,581	584	2,319,314	0	(864,122)	80,771	1,536,581	34
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from exercise of options, net			149				149
Net Proceeds (in Millions)		144	981,174			(2,687)	978,631
Conversion of Series A-4 preferred stock	11,503		11,503				11,503
Share-based compensation - amortization and forfeitures		4	9,301		252		9,557
Net income	31,471				31,321	60	31,381
Unrealized gain on interest rate swaps	0			(3,181)		(220)	(3,401)
Distributions	179,400				190,866	11,308	(202,174)
Balance at Dec. 31, 2016	$ 2,362,227	$ 732	$ 3,321,441	$ (3,181)	$ (1,023,415)	$ 66,616	$ 2,362,227	$ 34