Note 12 - Derivative Liabilities - Assumptions (Details)	Jan. 31, 2023 $ / shares	Jan. 31, 2023 $ / shares	Oct. 31, 2022 $ / shares	Jul. 31, 2022 $ / shares
Exercise Price (in dollars per share)	$ 2.93		$ 2.85	$ 1.92
Replacement Warrants [Member] | Measurement Input, Expected Dividend Rate [Member]
Derivative, measurement input	0.0000	0.0000
Replacement Warrants [Member] | Minimum [Member]
Exercise Price (in dollars per share) | (per share)	$ 1.08	$ 1.44
Replacement Warrants [Member] | Minimum [Member] | Measurement Input, Risk Free Interest Rate [Member]
Derivative, measurement input	0.0435	0.0435
Replacement Warrants [Member] | Minimum [Member] | Measurement Input, Price Volatility [Member]
Derivative, measurement input	0.5780	0.5780
Replacement Warrants [Member] | Minimum [Member] | Measurement Input, Expected Term [Member]
Derivative, measurement input	0.30	0.30
Replacement Warrants [Member] | Maximum [Member]
Exercise Price (in dollars per share) | (per share)	$ 3.33	$ 4.44
Replacement Warrants [Member] | Maximum [Member] | Measurement Input, Risk Free Interest Rate [Member]
Derivative, measurement input	0.0469	0.0469
Replacement Warrants [Member] | Maximum [Member] | Measurement Input, Price Volatility [Member]
Derivative, measurement input	0.8725	0.8725
Replacement Warrants [Member] | Maximum [Member] | Measurement Input, Expected Term [Member]
Derivative, measurement input	1.60	1.60