Condensed Consolidated Statement of Changes in Stockholders' Equity (Unaudited) - USD ($)	Common Stock [Member]	Retained Earnings [Member]	Total
Beginning balance, value at May. 31, 2020	$ 12,257,306	$ (364,104)	$ 11,893,202
Shares outstanding at May. 31, 2020	3,784,554
Shares issued to directors and officers upon vesting of RSUs	$ 0	0	0
Shares issued to directors and officers upon vesting of RSUs, shares	77,281
Stock-based compensation	$ 163,493	0	163,493
Net loss	0	(4,635,607)	(4,635,607)
Share repurchases	$ (234,517)		(234,517)
Share repurchases, shares	(72,101)
Repurchase of restricted stock units	$ (65,975)	0	$ (65,975)
Repurchase of restricted stock units, shares			(14,400)
Ending balance, value at Feb. 28, 2021	$ 12,120,307	(4,999,711)	$ 7,120,596
Shares outstanding at Feb. 28, 2021	3,775,334
Beginning balance, value at May. 31, 2021	$ 12,223,359	(8,453,776)	3,769,583
Shares outstanding at May. 31, 2021	3,786,502
Shares issued to directors and officers upon vesting of RSUs	$ 0	0	0
Shares issued to directors and officers upon vesting of RSUs, shares	32,268
Stock-based compensation	$ 95,016	0	95,016
Net loss	0	249,629	249,629
Ending balance, value at Feb. 28, 2022	$ 12,318,375	$ (8,204,147)	$ 4,114,228
Shares outstanding at Feb. 28, 2022	3,818,770