STOCK-BASED COMPENSATION (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Nov. 30, 2023	Nov. 30, 2022	Nov. 30, 2023	Nov. 30, 2022
Total stock-based compensation	$ 638	$ 793	$ 1,160	$ 1,503
Cost of Sales
Total stock-based compensation	101	85	164	177
Selling, General and Administrative
Total stock-based compensation	398	507	704	971
Research and Development
Total stock-based compensation	$ 139	$ 201	$ 292	$ 355

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479830/718-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Balance Type:	debit
Period Type:	duration