Note 12 - Capital Stock - Number of Shares Issued and Cash Received Upon Exercise of the Stock Options (Details) - USD ($)	3 Months Ended
	Oct. 31, 2021	Oct. 31, 2020
Number of Options Exercised on Cash Basis (in shares)	344,998	10,000
Number of Options Exercised on Forfeiture Basis (in shares)	685,545	18,500
Total Number of Options Exercised (in shares)	1,030,543	28,500
Number of Shares Issued on Cash Exercise (in shares)	344,998	10,000
Number of Shares Issued on Forfeiture Basis (in shares)	408,992	3,532
Total Number of Shares Issued Upon Exercise of Options (in shares)	753,990	13,532
Cash Received from Exercise of Stock Options	$ 383,779	$ 9,309
Total Intrinsic Value of Options Exercised	$ 1,905,216	$ 6,678