EARNINGS PER SHARE - Schedule of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Numerator:
Net earnings (basic)	$ 6,043	$ 4,634	$ 11,380	$ 8,993
Net earnings (diluted)	$ 6,043	$ 4,634	$ 11,380	$ 8,993
Denominator:
Weighted-average shares outstanding (basic) (in shares)	11,659,513	11,327,363	11,737,307	11,193,901
Effect of dilutive securities:
Common stock equivalent shares from stock options (in shares)	70,545	112,740	57,093	115,665
Weighted-average shares outstanding (diluted) (in shares)	11,730,058	11,440,103	11,794,400	11,309,566
Net earnings per share
Basic (in USD per share)	$ 0.52	$ 0.41	$ 0.97	$ 0.80
Diluted (in USD per share)	$ 0.52	$ 0.41	$ 0.97	$ 0.80

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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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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