Note 13 - Capital Stock - Summary of Stock Options Outstanding and Exercisable (Details) - $ / shares	6 Months Ended
	Jan. 31, 2023	Oct. 31, 2022	Jul. 31, 2022
Options Outstanding (in shares)	8,674,409	8,856,055	8,880,527
Options outstanding, weighted average exercise price (in dollars per share)	$ 1.65	$ 1.65	$ 1.58
Options outstanding, weighted average remaining contractual term (Year)	6 years 6 months 10 days
Options exercisable (in shares)	7,028,240
Options exercisable, weighted average exercise price (in dollars per share)	$ 1.37
Options exercisable, weighted average remaining contractual term (Year)	6 years 7 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)	7 years 7 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)	7 years 7 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)	2,690,000
Options outstanding, weighted average exercise price (in dollars per share)	$ 1.31
Options outstanding, weighted average remaining contractual term (Year)	4 years 2 months 26 days
Options exercisable (in shares)	2,248,332
Options exercisable, weighted average exercise price (in dollars per share)	$ 1.35
Options exercisable, weighted average remaining contractual term (Year)	3 years 7 months 9 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)	1,008,954
Options outstanding, weighted average exercise price (in dollars per share)	$ 2.23
Options outstanding, weighted average remaining contractual term (Year)	7 years 8 months 4 days
Options exercisable (in shares)	764,061
Options exercisable, weighted average exercise price (in dollars per share)	$ 2.23
Options exercisable, weighted average remaining contractual term (Year)	7 years 5 months 8 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)	1,378,331
Options outstanding, weighted average exercise price (in dollars per share)	$ 3.81
Options outstanding, weighted average remaining contractual term (Year)	8 years 10 months 13 days
Options exercisable (in shares)	423,098
Options exercisable, weighted average exercise price (in dollars per share)	$ 3.80
Options exercisable, weighted average remaining contractual term (Year)	7 years 10 months 2 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 8 months 23 days
Options exercisable (in shares)	625
Options exercisable, weighted average exercise price (in dollars per share)	$ 4.23
Options exercisable, weighted average remaining contractual term (Year)	9 years 8 months 23 days