EARNINGS PER SHARE - Schedule of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net earnings (basic)	$ 9,253	$ 10,134	$ 30,647	$ 17,487
Net earnings (diluted)	$ 9,253	$ 10,134	$ 30,647	$ 17,487
Denominator:
Weighted-average shares outstanding (basic) (in shares)	12,067,769	12,113,266	12,054,426	12,271,889
Effect of dilutive securities:
Common stock equivalent shares from stock options (in shares)	143,620		155,058
Weighted-average shares outstanding (diluted) (in shares)	12,211,389	12,113,266	12,209,484	12,271,889
Net earnings per share
Basic (in USD per share)	$ 0.77	$ 0.84	$ 2.54	$ 1.43
Diluted (in USD per share)	$ 0.76	$ 0.84	$ 2.51	$ 1.43