Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Total Shareholders’ Equity	Common Shares	Additional Paid - In Capital	Retained earnings (distributions in excess of retained earnings)	Noncontrolling Interest in Operating Partnership
Beginning Balance (in shares) at Dec. 31, 2016			38,367,014
Beginning Balance at Dec. 31, 2016	$ 681,590	$ 676,742	$ 380	$ 722,019	$ (45,657)	$ 4,848
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares pursuant to Equity Incentive Plan (in shares)			23,980
Issuance of shares pursuant to Equity Incentive Plan	500	500		500
Issuance of shares, net of offering costs (in shares)			6,665
Issuance of shares, net of offering costs	(63)	(63)		(63)
Issuance of restricted time-based shares (in shares)			5,000
Issuance of restricted time-based shares	0
Amortization of share based compensation	662	224		224		438
Dividends declared on common shares	(12,686)	(12,686)			(12,686)
Distributions declared on LTIP units	(207)					(207)
Reallocation of noncontrolling interest	0	164		164		(164)
Net income	4,644	4,613			4,613	31
Ending Balance (in shares) at Mar. 31, 2017			38,402,659
Ending Balance at Mar. 31, 2017	674,440	669,494	$ 380	722,844	(53,730)	4,946
Beginning Balance (in shares) at Dec. 31, 2017			45,375,266
Beginning Balance at Dec. 31, 2017	809,780	803,162	$ 450	871,730	(69,018)	6,618
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares pursuant to Equity Incentive Plan (in shares)			21,670
Issuance of shares pursuant to Equity Incentive Plan	500	500		500
Issuance of shares, net of offering costs (in shares)			472,664
Issuance of shares, net of offering costs	10,282	10,282	$ 9	10,273
Amortization of share based compensation	792	64		64		728
Dividends declared on common shares	(15,141)	(15,141)			(15,141)
Distributions declared on LTIP units	(283)					(283)
Reallocation of noncontrolling interest	0	19		19		(19)
Net income	2,868	2,848			2,848	20
Ending Balance (in shares) at Mar. 31, 2018			45,869,600
Ending Balance at Mar. 31, 2018	$ 808,798	$ 801,734	$ 459	$ 882,586	$ (81,311)	$ 7,064