Note 15 - Stock-based Compensation - Schedule of Outstanding RSUs (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares	12 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Balance, number of restricted stock units (in shares)	997,612	1,615,000	465,000
Balance, weighted average grant date fair value (in dollars per share)	$ 1.42	$ 0.92	$ 0.94
Granted, number of restricted stock units (in shares)	346,790	407,617	1,305,000
Granted, weighted average grant date fair value (in dollars per share)	$ 4.03	$ 2.15	$ 0.91
Vested, number of restricted stock units (in shares)	(508,368)	(1,025,005)	(155,000)
Vested, weighted average grant date fair value (in dollars per share)	$ 1.25	$ 0.91	$ 0.94
Balance, number of restricted stock units (in shares)	836,034	997,612	1,615,000
Balance, weighted average grant date fair value (in dollars per share)	$ 2.61	$ 1.42	$ 0.92