Note 13 - Capital Stock - Summary of Stock Options Outstanding and Exercisable (Details) - $ / shares	3 Months Ended
	Oct. 31, 2022	Jul. 31, 2022
Options Outstanding (in shares)	8,856,055	8,880,527
Options outstanding, weighted average exercise price (in dollars per share)	$ 1.65	$ 1.58
Options outstanding, weighted average remaining contractual term (Year)	6 years 8 months 19 days
Options exercisable (in shares)	6,830,492
Options exercisable, weighted average exercise price (in dollars per share)	$ 1.30
Options exercisable, weighted average remaining contractual term (Year)	6 years 21 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)	3,688,374
Options outstanding, weighted average exercise price (in dollars per share)	$ 0.92
Options outstanding, weighted average remaining contractual term (Year)	7 years 3 months 10 days
Options exercisable (in shares)	3,688,374
Options exercisable, weighted average exercise price (in dollars per share)	$ 0.92
Options exercisable, weighted average remaining contractual term (Year)	7 years 3 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)	2,703,500
Options outstanding, weighted average exercise price (in dollars per share)	$ 1.30
Options outstanding, weighted average remaining contractual term (Year)	4 years 5 months 19 days
Options exercisable (in shares)	2,261,832
Options exercisable, weighted average exercise price (in dollars per share)	$ 1.34
Options exercisable, weighted average remaining contractual term (Year)	3 years 9 months 29 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)	1,028,814
Options outstanding, weighted average exercise price (in dollars per share)	$ 2.22
Options outstanding, weighted average remaining contractual term (Year)	7 years 10 months 28 days
Options exercisable (in shares)	554,643
Options exercisable, weighted average exercise price (in dollars per share)	$ 2.22
Options exercisable, weighted average remaining contractual term (Year)	7 years 2 months 23 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)	1,430,367
Options outstanding, weighted average exercise price (in dollars per share)	$ 3.80
Options outstanding, weighted average remaining contractual term (Year)	8 years 8 months 4 days
Options exercisable (in shares)	325,643
Options exercisable, weighted average exercise price (in dollars per share)	$ 3.77
Options exercisable, weighted average remaining contractual term (Year)	5 years 9 months 21 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 11 months 23 days
Options exercisable (in shares)	0
Options exercisable, weighted average exercise price (in dollars per share)	$ 4.23
Options exercisable, weighted average remaining contractual term (Year)	9 years 11 months 23 days