Note 7 - Property, Plant and Equipment, Net of Accumulated Depreciation (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Precious Metals	$ 3,100	$ 3,400
Depletion	35	27	$ 28
Interest Costs Capitalized	$ 40	$ 48	$ 36