Acquisitions and Dispositions - Unaudited Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Business Acquisition [Line Items]
Revenue	$ 106,047	$ 79,183
Net income	12,009	7,298
Net income available to common shareholders	$ 11,065	$ 6,756
Earnings per share - basic (in dollars per share)	$ 0.06	$ 0.04
Earnings per share - diluted (in dollars per share)	$ 0.06	$ 0.04
Weighted average number of shares outstanding - basic	181,809,570	181,809,570
Weighted average number of shares outstanding - diluted (in shares)	187,317,243	187,317,243
Operating Partnership
Business Acquisition [Line Items]
Revenue	$ 106,047	$ 79,183
Net income	12,009	7,298
Net income available to common shareholders	$ 11,411	$ 6,920
Earnings per unit - basic (in dollars per unit)	$ 0.06	$ 0.04
Earnings per unit - diluted (in dollars per unit)	$ 0.06	$ 0.04
Weighted average limited partnership units outstanding, basic (in shares)	187,264,064	187,264,064
Denominator for earnings per unit - diluted (in shares)	187,317,243	187,317,243