Note 13 - Capital Stock - Summary of Stock-based Compensation Expense (Details) - USD ($)	12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2018
Share-based Payment Arrangement, Noncash Expense, Total	$ 3,493,218	$ 2,948,041	$ 3,504,058
Common stock issued	1,122,917	1,361,944	1,711,579
Settlement of share issuance obligation	(15,189)		(127,615)
Consultants [Member]
Common stock issued for consulting services	539,552	644,307	740,640
Amortization of expenses	240,912	153,549	582,842
Share-based Payment Arrangement, Noncash Expense, Total	780,464	797,856	1,323,482
Management [Member]
Amortization of expenses	644,516	516,266	284,556
Share-based Payment Arrangement, Noncash Expense, Total	1,452,518	785,954	987,061
Common stock issued	225,217	269,688	702,505
Management [Member] | Restricted Stock Units (RSUs) and Performance Restricted Stock Units (PRSUs) [Member]
Amortization of expenses	582,785
Employees [Member]
Amortization of expenses	640,011	689,743	547,231
Share-based Payment Arrangement, Noncash Expense, Total	1,275,425	1,364,231	1,321,130
Common stock issued	$ 635,414	$ 674,488	$ 773,899