CONDENSED CONSOLIDATED STATEMENT OF EQUITY (USD $) In Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interests [Member]
Beginning balance at Dec. 31, 2013	$ 1,592,082	$ 2,067	$ 1,874,539	$ (287,138)	$ 2,613	$ 1
Beginning balance, shares at Dec. 31, 2013	206,743	206,743
Net income	12,431			12,431
Unrealized loss on derivative instruments	(3,642)				(3,642)
Issuance of common stock	48,587	50	48,537
Issuance of common stock, shares		4,991
Share-based compensation	442		442
Offering costs	(850)		(850)
Redemptions of common stock	(14,814)	(15)	(14,799)
Redemptions of common stock, shares	(1,480)	(1,480)
Distributions to stockholders	(98,131)			(98,131)
Ending balance at Sep. 30, 2014	$ 1,536,105	$ 2,102	$ 1,907,869	$ (372,838)	$ (1,029)	$ 1
Ending balance, shares at Sep. 30, 2014	210,254	210,254