Note 4 - Inventories (Details Textual)	1 Months Ended	3 Months Ended	9 Months Ended
	Jun. 08, 2021 USD ($) lb	Apr. 30, 2021 lb	Apr. 30, 2021 USD ($)	Apr. 30, 2020 USD ($)
Increase (Decrease) in Inventories, Total | $			$ 26,193,818
Uranium Inventory [Member]
Increase in Purchase Obligations, Mass (Pound)		2,305,000
Inventory, Increase from Purchases, Mass (Pound)		900,000
Uranium Inventory [Member] | Subsequent Event [Member]
Increase in Purchase Obligations, Mass (Pound)	200,000
Inventory, Increase from Purchases, Mass (Pound)	100,000
Increase (Decrease) in Inventories, Total | $	$ 2,745,000