CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $) In Thousands, except Share data	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit and Distributions	Total Stockholders' Equity	Operating Partnership	Joint Venture
Balance at Dec. 31, 2011	$ 319,449	$ 20	$ 273	$ 288,902		$ (11,020)	$ 278,175	$ 41,274
Balance (in shares) at Dec. 31, 2011		2,000,000	27,278,000
Registration and offering costs	(707)			(707)			(707)
Common stock redemption of common units			40	(3,670)			(3,630)	3,630
Common stock redemption of common units (in shares)			4,015,192
Dividends paid	(16,129)					(13,540)	(13,540)	(2,589)
Equity-based compensation	783		2	644			646	137
Equity-based compensation (in shares)			208,027
Other comprehensive income (loss)	(521)				(431)		(431)	(90)
Net income (loss)	(1,521)					(254)	(254)	(1,267)
Balance at Sep. 30, 2012	301,354	20	315	285,169	(431)	(24,814)	260,259	41,095
Balance (in shares) at Sep. 30, 2012		2,000,000	31,501,219
Balance at Dec. 31, 2012	473,537	50	462	468,820	(528)	(31,985)	436,819	36,718
Balance (in shares) at Dec. 31, 2012		5,000,000	46,159,652
Net proceeds from sale of common stock	300,166		345	299,821			300,166
Net proceeds from sale of common stock (in shares)			34,500,000
Net proceeds from sale of preferred stock	81,723	34		81,689			81,723
Net proceeds from sale of preferred stock (in shares)		3,400,000
Common stock redemption of common units			25	15,365			15,390	(15,390)
Common stock redemption of common units (in shares)			2,466,404
Contribution by noncontrolling interests in joint venture	7,500								7,500
Dividends paid	(33,748)					(32,735)	(32,735)	(1,013)
Equity-based compensation	1,616		3	1,613			1,616
Equity-based compensation (in shares)			325,758
Other comprehensive income (loss)	(1,310)				(1,253)		(1,253)	(57)
Net income (loss)	7,973					7,757	7,757	(108)	324
Balance at Sep. 30, 2013	$ 837,457	$ 84	$ 835	$ 867,308	$ (1,781)	$ (56,963)	$ 809,483	$ 20,150	$ 7,824
Balance (in shares) at Sep. 30, 2013		8,400,000	83,451,814