Note 16 - Capital Stock - Warrants Outstanding and Exercisable (Details) - $ / shares	12 Months Ended
	Jul. 31, 2023	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Weighted Average Exercise Price (in dollars per share)	$ 3.31	$ 1.92	$ 1.90	$ 2.03
Number of Warrants Outstanding (in shares)	3,857,030	3,615,454	5,387,323	7,721,981
Warrants 1 [Member]
Weighted Average Exercise Price (in dollars per share)	$ 3.27
Number of Warrants Outstanding (in shares)	3,675,212
Weighted Average Remaining Contractual Life (Year)	1 year 1 month 9 days
Warrants 2 [Member]
Weighted Average Exercise Price (in dollars per share)	$ 4.13
Number of Warrants Outstanding (in shares)	181,818
Weighted Average Remaining Contractual Life (Year)	2 years 8 months 4 days
Warrants 3 [Member]
Weighted Average Exercise Price (in dollars per share)	$ 3.31
Number of Warrants Outstanding (in shares)	3,857,030
Weighted Average Remaining Contractual Life (Year)	1 year 2 months 4 days