STOCKBASED COMPENSATION (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2022	Nov. 30, 2021	Nov. 30, 2022	Nov. 30, 2021
Total stock-based compensation	$ 793	$ 718	$ 1,503	$ 1,306
Cost of Sales
Total stock-based compensation	85	76	177	158
Selling, General and Administrative
Total stock-based compensation	507	377	971	772
Research and Development
Total stock-based compensation	$ 201	$ 265	$ 355	$ 376