FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 1) - USD ($) $ in Thousands	Feb. 29, 2024	May 31, 2023	Feb. 28, 2023	May 31, 2022
Total cash and cash equivalents	$ 47,581	$ 30,054
Total cash, cash equivalents and investments	47,731	30,204	$ 17,338	$ 31,564
Short-term Investments	0	17,853
Cost [Member]
Cash	3,542	3,182
Total cash and cash equivalents	47,581	30,054
Total cash, cash equivalents and investments	47,731	48,074
Cost [Member] | Money Market Funds
Cash equivalents	44,039	26,872
Long-term investments	150	150
Cost [Member] | U S Treasury Securities [Member]
Short-term Investments		17,870
Gross Unrealized Loss
Cash	0	0
Total cash and cash equivalents	0	0
Total cash, cash equivalents and investments	0	(17)
Gross Unrealized Loss | Money Market Funds
Cash equivalents	0	0
Long-term investments	0	0
Gross Unrealized Loss | U S Treasury Securities [Member]
Short-term Investments		(17)
Estimated Fair Value [Member]
Cash	3,542	3,182
Total cash and cash equivalents	47,581	30,054
Total cash, cash equivalents and investments	47,731	48,057
Estimated Fair Value [Member] | Money Market Funds
Cash equivalents	44,039	26,872
Long-term investments	$ 150	150
Estimated Fair Value [Member] | U S Treasury Securities [Member]
Short-term Investments		$ 17,853