Note 9 - Investments in Equity Securities - Changes in Investments in Equity Securities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jan. 31, 2025	Jan. 31, 2024	Jan. 31, 2025	Jan. 31, 2024
Balance			$ 75,264
Sale of investment in publicly listed companies			(54,372)	$ (3,008)
Investment in public listed companies			10,455	5,548
Fair value loss on equity securities	$ (7,967)	$ 20,076	(18,317)	$ 37,389
Foreign exchange difference			(5)
Balance	$ 13,025		13,025
Investment in Public Listed Companies [Member]
Sale of investment in publicly listed companies			(54,372)
Investment in public listed companies			$ 10,455