Note 15 - Stock-based Compensation - Schedule of Outstanding Stock Options (Details) - $ / shares	12 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Balance, number of stock options (in shares)	10,404,333	15,514,750	15,738,350
Balance, Weighted Average Exercise Price (in dollars per share)	$ 1.21	$ 1.13	$ 1.30
Granted, number of stock options (in shares)	1,279,692	959,588	6,163,900
Granted, Weighted Average Exercise Price (in dollars per share)	$ 3.80	$ 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)	(75,000)	(1,365,000)	(6,208,156)
Expired, Weighted Average Exercise Price (in dollars per share)	$ 2.50	$ 1.48	$ 1.39
Exercised, number of stock options (in shares)	(2,728,498)	(4,705,005)	0
Exercised Options, Weighted Average Exercise Price (in dollars per share)	$ 1.17	$ 1.09
Exercised, number of stock options (in shares)	(2,728,498)	(4,705,005)	0
Balance, number of stock options (in shares)	8,880,527	10,404,333	15,514,750
Balance, Weighted Average Exercise Price (in dollars per share)	$ 1.58	$ 1.21	$ 1.13