Condensed Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Total Stockholders' Equity [Member]	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Cumulative Distributions in Excess of Net Income [Member]	Accumulated Other Comprehensive Loss [Member]	Noncontrolling Interests [Member]	Common Stock [Member]	Common Stock [Member] Total Stockholders' Equity [Member]	Common Stock [Member] Common Stock [Member]	Common Stock [Member] Additional Paid-in Capital [Member]
Beginning balance (in shares) at Dec. 31, 2015			5,750,000	65,182,335
Beginning balance at Dec. 31, 2015	$ 1,053,876	$ 1,053,770	$ 58	$ 652	$ 1,202,541	$ (142,148)	$ (7,333)	$ 106
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(15,743)	(15,711)				(15,711)		(32)
Other comprehensive loss	(2,065)	(2,065)					(2,065)
Amortization of stock-based compensation	1,938	1,938			1,938
Common stock issuance, net (in shares)											90,883
Common stock issuance, net									$ (1,088)	$ (1,088)	$ 1	$ (1,089)
Preferred dividends	(2,561)	(2,561)				(2,561)
Common dividends	(26,859)	(26,859)				(26,859)
Ending balance (in shares) at Mar. 31, 2016			5,750,000	65,273,218
Ending balance at Mar. 31, 2016	1,007,498	1,007,424	$ 58	$ 653	1,203,390	(187,279)	(9,398)	74
Beginning balance (in shares) at Dec. 31, 2016			5,750,000	65,285,614
Beginning balance at Dec. 31, 2016	1,015,609	1,015,574	$ 58	$ 653	1,208,862	(192,201)	(1,798)	35
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	18,791	18,823				18,823		(32)
Other comprehensive loss	170	170					170
Amortization of stock-based compensation	2,860	2,860			2,860
Common stock issuance, net (in shares)											125,054
Common stock issuance, net									$ (2,814)	$ (2,814)	$ 1	$ (2,815)
Preferred dividends	(2,561)	(2,561)				(2,561)
Common dividends	(27,702)	(27,702)				(27,702)
Ending balance (in shares) at Mar. 31, 2017			5,750,000	65,410,668
Ending balance at Mar. 31, 2017	$ 1,004,353	$ 1,004,350	$ 58	$ 654	$ 1,208,907	$ (203,641)	$ (1,628)	$ 3