Note 3 - Earnings (Loss) Per Share - Schedule of Basic and Diluted Earnings Per Share (Details) - USD ($)	3 Months Ended		9 Months Ended
	Feb. 28, 2026	Feb. 28, 2025	Feb. 28, 2026	Feb. 28, 2025
Net income (loss) attributable to common stockholders	$ (2,802,078)	$ 849,867	$ (5,965,195)	$ 691,942
Weighted-average shares outstanding - basic (in shares)	27,270,701	28,097,494	27,273,160	28,220,051
Earnings (loss) per share of common stock - basic (in dollars per share)	$ (0.1)	$ 0.03	$ (0.22)	$ 0.02
Incremental shares from assumed conversion of options warrants and preferred stock, as appropriate (in shares)	0	495,099	0	495,892
Weighted average common stock outstanding - diluted (in shares)	27,270,701	28,592,593	27,273,160	28,715,943
Earnings (Loss) per share of common stock - diluted (in dollars per share)	$ (0.1)	$ 0.03	$ (0.22)	$ 0.02