Note 10 - Fair Value Measurement - Assets and Liabilities Accounted for at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Other, net	$ 10,695	$ 8,149
Fair Value, Recurring [Member]
Total assets	177,898	267,177
Total liabilities	22,191	37,881
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Recurring [Member]
Money market funds and other bank deposits	104,743	210,010
Equity securities – mining industry	24,018	14,470
Certificates of deposit and other deposits	1,164	1,053
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Recurring [Member]
Other, net	45,146	36,437
Metal forward and put option contracts	$ 1,309	$ 0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Assets	Assets
Foreign exchange contracts	$ 1,518	$ 5,207
Metal forward and put option contracts	$ 14,643	$ 37,873
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Liabilities	Liabilities
Foreign exchange contracts	$ 7,548	$ 8

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Fair value of financial and nonfinancial obligations.

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Amount due from parties in nontrade transactions, classified as other.

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