Note 14 - Stock-based Compensation - Schedule of Outstanding Stock Options (Details) - $ / shares	12 Months Ended
	Jul. 31, 2021	Jul. 30, 2021	Jul. 31, 2020
Balance, number of stock options (in shares)	15,514,750	15,514,750	15,738,350
Balance, Weighted Average Exercise Price (in dollars per share)	$ 1.13	$ 1.13	$ 1.30
Granted, number of stock options (in shares)	959,588	959,588	6,163,900
Granted, Weighted Average Exercise Price (in dollars per share)	$ 2.21		$ 0.95
Cancelled/Forfeited, number of stock options (in shares)			(179,344)
Cancelled/Forfeited, Weighted Average Exercise Price (in dollars per share)			$ 1.02
Expired, number of stock options (in shares)	(1,365,000)		(6,208,156)
Expired, Weighted Average Exercise Price (in dollars per share)	$ 1.48		$ 1.39
Exercised (in shares)	(4,705,005)
Exercised Options, Weighted Average Exercise Price (in dollars per share)	$ 1.09
Balance, number of stock options (in shares)	10,404,333		15,514,750
Balance, Weighted Average Exercise Price (in dollars per share)	$ 1.21		$ 1.13