Note 13 - Sales and Service Revenue and Cost of Sales and Services - Sales and Service Revenue and Cost of Sales and Service Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2024	Apr. 30, 2023	Apr. 30, 2024	Apr. 30, 2023
Revenue	$ 0	$ 20,217	$ 224	$ 125,440
Cost of revenues	0	(13,998)	(187)	(90,793)
Sale of Inventory [Member]
Revenue	0	20,095	0	125,140
Cost of revenues	0	(13,896)	0	(90,543)
Toll Processing Services [Member]
Revenue	0	122	224	300
Cost of revenues	$ 0	$ (102)	$ (187)	$ (250)