EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2021	Nov. 30, 2020	Nov. 30, 2021	Nov. 30, 2020
Net income (loss)	$ 717	$ (1,966)	$ 1,413	$ (1,859)
Denominator for basic net income (loss) per share: Weighted average shares outstanding (in thousands)	26,205	23,396	25,102	23,322
Denominator for diluted net income (loss) per share (in thousands)	28,342	23,396	26,849	23,322
Basic net income (loss) per share	$ 0.03	$ (0.08)	$ 0.06	$ (0.08)
Diluted net income (loss) per share	$ 0.03	$ (0.08)	$ 0.05	$ (0.08)
Numerator [Member]
Net income (loss)	$ 717	$ (1,966)	$ 1,413	$ (1,859)
Denominator [Member]
Denominator for basic net income (loss) per share: Weighted average shares outstanding (in thousands)	26,205	23,396	25,102	23,322
Shares used in basic net income (loss) per share calculation (in thousands)	26,205	23,396	25,102	23,322
Effect of dilutive securities (in thousands)	2,137		1,747
Denominator for diluted net income (loss) per share (in thousands)	28,342	23,396	26,849	23,322
Basic net income (loss) per share	$ 0.03	$ (0.08)	$ 0.06	$ (0.08)
Diluted net income (loss) per share	$ 0.03	$ (0.08)	$ 0.05	$ (0.08)