Note 13 - Capital Stock - Summary of Stock Options Outstanding and Exercisable (Details) - $ / shares	3 Months Ended
	Apr. 30, 2023	Jan. 31, 2023	Oct. 31, 2022	Jul. 31, 2022
Options Outstanding (in shares)	8,436,909	8,674,409	8,856,055	8,880,527
Options outstanding, weighted average exercise price (in dollars per share)	$ 1.67	$ 1.65	$ 1.65	$ 1.58
Options outstanding, weighted average remaining contractual term (Year)	6 years 5 months 1 day
Options exercisable (in shares)	6,706,420
Options exercisable, weighted average exercise price (in dollars per share)	$ 1.36
Options exercisable, weighted average remaining contractual term (Year)	5 years 11 months 12 days
Exercise Price Range 1 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 0.80
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 0.99
Options Outstanding (in shares)	3,592,124
Options outstanding, weighted average exercise price (in dollars per share)	$ 0.92
Options outstanding, weighted average remaining contractual term (Year)	6 years 9 months 10 days
Options exercisable (in shares)	3,592,124
Options exercisable, weighted average exercise price (in dollars per share)	$ 0.92
Options exercisable, weighted average remaining contractual term (Year)	6 years 9 months 10 days
Exercise Price Range 2 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 1.00
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 1.99
Options Outstanding (in shares)	2,442,500
Options outstanding, weighted average exercise price (in dollars per share)	$ 1.29
Options outstanding, weighted average remaining contractual term (Year)	4 years 1 month 13 days
Options exercisable (in shares)	2,000,832
Options exercisable, weighted average exercise price (in dollars per share)	$ 1.33
Options exercisable, weighted average remaining contractual term (Year)	3 years 5 months 8 days
Exercise Price Range 3 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 2.00
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 2.99
Options Outstanding (in shares)	918,954
Options outstanding, weighted average exercise price (in dollars per share)	$ 2.22
Options outstanding, weighted average remaining contractual term (Year)	7 years 11 months 15 days
Options exercisable (in shares)	687,183
Options exercisable, weighted average exercise price (in dollars per share)	$ 2.22
Options exercisable, weighted average remaining contractual term (Year)	7 years 10 months 13 days
Exercise Price Range 4 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 3.00
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 3.99
Options Outstanding (in shares)	1,478,331
Options outstanding, weighted average exercise price (in dollars per share)	$ 3.76
Options outstanding, weighted average remaining contractual term (Year)	8 years 4 months 13 days
Options exercisable (in shares)	425,031
Options exercisable, weighted average exercise price (in dollars per share)	$ 3.78
Options exercisable, weighted average remaining contractual term (Year)	7 years 7 months 9 days
Exercise Price Range 5 [Member]
Range of Exercise Prices, Lower Limit (in dollars per share)	$ 4.00
Range of Exercise Prices, Upper Limit (in dollars per share)	$ 4.23
Options Outstanding (in shares)	5,000
Options outstanding, weighted average exercise price (in dollars per share)	$ 4.23
Options outstanding, weighted average remaining contractual term (Year)	9 years 5 months 26 days
Options exercisable (in shares)	1,250
Options exercisable, weighted average exercise price (in dollars per share)	$ 4.23
Options exercisable, weighted average remaining contractual term (Year)	9 years 5 months 26 days