EARNINGS (LOSS) PER SHARE - Computation of Basic and Diluted Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
EARNINGS (LOSS) PER SHARE
Net income (loss)	$ 3,597	$ (2,551)
Denominator:
Denominator for basic earnings (loss) per share - weighted average shares	8,841	8,633
Effect of dilutive securities:
Employee restricted stock and incentive stock options	166
Denominator for diluted earnings (loss) per share - adjusted weighted average shares and assumed conversion (in shares)	9,007	8,633
Basic earnings (loss) per share (in dollars per share)	$ 0.41	$ (0.30)
Diluted earnings (loss) per share (in dollars per share)	$ 0.40	$ (0.30)
Weighted average anti-dilutive employee restricted stock and incentive stock options (in shares)	234	439