CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2018		39,303,710
Beginning balance at Dec. 31, 2018	$ 733,228	$ 395	$ 827,558	$ (459)	$ (94,266)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock (in shares)		1,161,580
Issuance of common stock	19,409	$ 11	19,398
Common stock repurchases (in shares)		(387,530)
Common stock repurchases	(7,207)	$ (4)	(7,203)
Common stock issued through distribution reinvestment plan (in shares)		180,906
Common stock issued through distribution reinvestment plan	3,392	$ 2	3,390
Share-based compensation	39		39
Offering costs	(382)		(382)
Net income (loss)	19,890				19,890
Distributions declared	(17,449)				(17,449)
Other comprehensive income	145			145
Ending balance (in shares) at Mar. 31, 2019		40,258,666
Ending balance at Mar. 31, 2019	751,065	$ 404	842,800	(314)	(91,825)
Beginning balance (in shares) at Dec. 31, 2019		43,916,815
Beginning balance at Dec. 31, 2019	816,805	$ 441	903,310	(978)	(85,968)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock (in shares)		650,034
Issuance of common stock	10,862	$ 7	10,855
Common stock repurchases (in shares)		(361,829)
Common stock repurchases	(6,715)	$ (4)	(6,711)
Common stock issued through distribution reinvestment plan (in shares)		191,326
Common stock issued through distribution reinvestment plan	3,549	$ 1	3,548
Share-based compensation	39		39
Offering costs	(136)		(136)
Net income (loss)	(7,400)				(7,400)
Distributions declared	(20,371)				(20,371)
Other comprehensive income	(67,607)			(67,607)
Ending balance (in shares) at Mar. 31, 2020		44,396,346
Ending balance at Mar. 31, 2020	$ 721,265	$ 445	$ 910,905	$ (68,585)	$ (121,500)