Note 10 - Product Inventories - Schedule of Our Major Components of Product Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Inventory [Line Items]
Product inventories	$ 37,414	$ 28,823
Concentrates
Inventory [Line Items]
Product inventories	16,423	13,328
Stockpiled ore
Inventory [Line Items]
Product inventories	8,870	7,168
In-process
Inventory [Line Items]
Product inventories	$ 12,121	$ 8,327