Earnings Per Share - Reconciliation of Amounts Used in Calculating Basic and Diluted Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator:
Net income	$ (2,349)	$ 10,002	$ 9,437	$ 1,613	$ (174)	$ 14,580	$ 13,387	$ 2,848	$ 18,703	$ 30,641	$ 29,478
Dividends paid on unvested shares and LTIP units									(297)	(310)	(235)
Net income attributable to common shareholders									$ 18,406	$ 30,331	$ 29,243
Denominator:
Weighted average number of common shares - basic (in shares)	46,919,035	46,913,922	46,760,016	46,556,710	46,513,688	46,149,765	45,867,625	45,753,792	46,788,784	46,073,515	39,859,143
Effect of dilutive securities:
Unvested shares (in shares)									234,496	170,145	253,123
Weighted average number of common shares - diluted (In shares)	47,220,671	47,152,166	46,976,999	46,734,958	46,765,797	46,384,969	46,084,688	46,022,690	47,023,280	46,243,660	40,112,266
Basic income per Common Share:
Net income attributable to common shareholders per weighted average common share (in dollars per share)	$ (0.05)	$ 0.21	$ 0.20	$ 0.03	$ 0	$ 0.31	$ 0.29	$ 0.06	$ 0.39	$ 0.66	$ 0.73
Diluted income per Common Share:
Net income attributable to common shareholders per weighted average common share (in dollars per share)	$ (0.05)	$ 0.21	$ 0.20	$ 0.03	$ 0	$ 0.31	$ 0.29	$ 0.06	$ 0.39	$ 0.66	$ 0.73