Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Common Shares	Additional Paid - In Capital	Retained earnings (distributions in excess of retained earnings)	Total Shareholders’ Equity	Noncontrolling Interest in Operating Partnership
Beginning Balance (in shares) at Dec. 31, 2014		34,173,691
Beginning Balance at Dec. 31, 2014	$ 591,952	$ 339	$ 599,318	$ (11,120)	$ 588,537	$ 3,415
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares pursuant to Equity Incentive Plan (in shares)		14,113
Issuance of shares pursuant to Equity Incentive Plan	412		412		412
Issuance of shares, net of offering costs of $8 in 2016 and $2,039 in 2015 (in shares)		4,026,704
Issuance of shares, net of offering costs of $8 in 2016 and $2,039 in 2015	118,758	$ 40	118,718		118,758
Issuance of restricted time-based shares		49,110
Issuance of performance based shares		44,274
Repurchase of common shares (in shares)		(763)
Repurchase of common shares	(22)		(22)		(22)
Amortization of share based compensation	1,690		1,182		1,182	508
Dividends declared on common shares ($0.97 per share) in 2016 and ($0.90 per share) in 2015	(34,539)			(34,539)	(34,539)
Distributions declared on LTIP units ($0.97 per unit) in 2016 and ($0.90 per unit) in 2015	(305)					(305)
Reallocation of noncontrolling interest	0		(286)		(286)	286
Net income	28,657			28,476	28,476	181
Ending Balance (in shares) at Sep. 30, 2015		38,307,129
Ending Balance at Sep. 30, 2015	706,603	$ 379	719,322	(17,183)	702,518	4,085
Beginning Balance (in shares) at Dec. 31, 2015		38,308,937
Beginning Balance at Dec. 31, 2015	697,002	$ 379	719,773	(27,281)	692,871	4,131
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares pursuant to Equity Incentive Plan (in shares)		26,488
Issuance of shares pursuant to Equity Incentive Plan	550		550		550
Issuance of shares, net of offering costs of $8 in 2016 and $2,039 in 2015 (in shares)		16,454
Issuance of shares, net of offering costs of $8 in 2016 and $2,039 in 2015	337	$ 1	336		337
Issuance of restricted time-based shares		7,851
Amortization of share based compensation	1,879		963		963	916
Dividends declared on common shares ($0.97 per share) in 2016 and ($0.90 per share) in 2015	(37,266)			(37,266)	(37,266)
Distributions declared on LTIP units ($0.97 per unit) in 2016 and ($0.90 per unit) in 2015	(537)					(537)
Reallocation of noncontrolling interest	0		11		11	(11)
Net income	29,018			28,823	28,823	195
Ending Balance (in shares) at Sep. 30, 2016		38,359,730
Ending Balance at Sep. 30, 2016	$ 690,983	$ 380	$ 721,633	$ (35,724)	$ 686,289	$ 4,694