Earnings Per Common Share - Reconciliation of Weighted-Average Common Shares Outstanding Used in Calculation of Basic EPS to Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net income	$ 16,053	$ 14,607
Less: Net income allocated to participating securities	(86)	(126)
Numerator for basic and diluted earnings available to common stockholders	$ 15,967	$ 14,481
Denominator:
Weighted-average basic common shares outstanding (in shares)	88,010	75,504
Weighted-average diluted common shares outstanding (in shares)	88,010	75,504
Earnings per common share, basic (in usd per share)	$ 0.18	$ 0.19
Earnings per common share, diluted (in usd per share)	$ 0.18	$ 0.19