4. EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Aug. 31, 2019	Aug. 31, 2018
Earnings Per Share [Abstract]
Net loss	$ (413)	$ (1,515)
Denominator for basic net loss per share: Weighted average shares outstanding (in thousands)	22,708	22,190
Shares used in basic net loss per share calculation (in thousands)	22,708	22,190
Effect of dilutive securities (in thousands)	0	0
Denominator for diluted net loss per share (in thousands)	22,708	22,190
Basic net loss per share	$ (0.02)	$ (0.07)
Diluted net loss per share	$ (0.02)	$ (0.07)