Consolidated Statements of Stockholders' Equity - USD ($)	Common Stock	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Total
Beginning balance, shares at May. 31, 2018	3,994,545
Beginning balance at May. 31, 2018	$ 13,085,652	$ (536,307)	$ (3,033,689)	$ 9,515,656
Exercise of stock options, shares	38,333			38,333
Exercise of stock options	$ 65,166			$ 65,166
Stock-based compensation	94,621			94,621
Net income (loss)			(1,210,990)	(1,210,990)
Other comprehensive income		8,480		8,480
Ending balance, shares at May. 31, 2019	4,032,878
Ending balance at May. 31, 2019	$ 13,245,439	(527,827)	(4,244,679)	8,472,933
Stock compensation expense for restricted stock units granted to employees and directors	$ 354,048			354,048
Repurchase of common stock, shares	(418,051)
Repurchase of common stock	$ (1,350,681)			(1,350,681)
Exercise of stock options, shares	33,166
Exercise of stock options	$ 8,500			8,500
Restricted stock units exercised, shares	136,561
Restricted stock units exercised				0
Net income (loss)			3,880,575	3,880,575
Other comprehensive income		527,827		527,827
Ending balance, shares at May. 31, 2020	3,784,554
Ending balance at May. 31, 2020	$ 12,257,306	$ 0	$ (364,104)	$ 11,893,202