Note 12 - Stock-based Compensation - Summary of Stock Options Assumptions (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jan. 31, 2019	Jan. 31, 2019
Options Granted (in shares)	40,000
Exercise Price (in dollars per share)	$ 1.25
Term (Year)	5 years
Employee Stock Option [Member]
Options Granted (in shares)		40,000
Exercise Price (in dollars per share)		$ 1.25
Term (Year)		5 years
Fair Value of Options Granted		$ 24,164
Expected Life (years) (Year)		3 years 255 days
Risk-Free Interest Rate		2.34%
Dividend Yield		0.00%
Expected Volatility Rate		63.70%