Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share
Net income attributable to common shares	$ 20,671	$ 19,535	$ 38,519	$ 39,196
Weighted-average common shares outstanding - basic	39,873,260	36,463,421	38,604,576	36,405,921
Effect of potentially dilutive common shares:
Weighted-average common shares outstanding - diluted	39,993,011	36,618,533	38,759,072	36,580,547
Net income per share attributable to common shares
Basic	$ 0.52	$ 0.54	$ 1.00	$ 1.08
Diluted	$ 0.52	$ 0.53	$ 0.99	$ 1.07
Weighted-average potentially dilutive securities excluded in calculation of basic and diluted income (loss) per share	566	228	2,074	26,749
Stock Options
Effect of potentially dilutive common shares:
Potentially dilutive common shares	20,065	38,741	22,708	38,886
Restricted awards
Effect of potentially dilutive common shares:
Potentially dilutive common shares	99,686	116,371	131,788	135,740

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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