NET INCOME PER COMMON SHARE - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Numerator:
Net income	$ 38,155	$ 31,474
Adjustment for Basic EPS:
Earnings allocated to unvested shareholders	(339)	(325)
Adjusted net income	$ 37,816	$ 31,149
Denominator:
Weighted average common shares outstanding – Basic	47,093,033	46,892,914
Effect of dilutive shares:
Common stock equivalents arising from stock options and ESPP	441	800
Restricted stock awards and units and performance units	29,355	38,285
Weighted average common shares outstanding – Diluted	47,122,829	46,931,999
Basic	$ 0.80	$ 0.66
Diluted	$ 0.80	$ 0.66

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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