SUBSEQUENT EVENTS (Details) - Subsequent Event [Member]	3 Months Ended
	Aug. 31, 2021 USD ($) $ / shares shares
SUBSEQUENT EVENTS (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | shares	1,500
Share-based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Exercise Price | $ / shares	$ 2.68
Proceeds from Stock Options Exercised | $	$ 4,000
Stock Issued During Period, Shares, New Issues | shares	201,553
Share Price | $ / shares	$ 4.16
Proceeds from Issuance of Common Stock | $	$ 824,000