Note 17 - Unrealized Loss on Equity Securities - Black-Sholes Valuation Model (Details)	Jul. 31, 2022
Measurement Input, Risk Free Interest Rate [Member]
Equity securities, measurement input	0.0259
Measurement Input, Price Volatility [Member]
Equity securities, measurement input	0.6476
Measurement Input, Expected Term [Member]
Equity securities, measurement input	0.0478
Measurement Input, Discount Rate [Member]
Equity securities, measurement input	0