Note 2 - Significant Accounting Policies - Schedule of Earnings Per Share (Details) - USD ($)	3 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Net income applicable to Common Stockholders	$ 1,138,501	$ 800,206
Weighted average shares, basic (in shares)	18,465,000	19,383,000
Warrants to purchase Common Stock (in shares)	288,000	286,000
Weighted average shares, diluted (in shares)	18,753,000	19,669,000
Basic (in dollars per share)	$ 0.06	$ 0.04
Diluted (in dollars per share)	$ 0.06	$ 0.04