Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share
Net income attributable to common shares	$ 17,848	$ 19,661
Weighted-average common shares outstanding - basic	37,335,892	36,347,781
Effect of potentially dilutive common shares:
Weighted-average common shares outstanding - diluted	37,504,349	36,547,065
Net income per share attributable to common shares
Basic	$ 0.48	$ 0.54
Diluted	$ 0.48	$ 0.54
Weighted-average potentially dilutive securities excluded in calculation of basic and diluted income (loss) per share	2,054	39,754
Stock Options
Effect of potentially dilutive common shares:
Potentially dilutive common shares	25,298	38,921
Restricted awards
Effect of potentially dilutive common shares:
Potentially dilutive common shares	143,159	160,363