v3.26.1
Note 10 - Fair Value Measurement - Assets and Liabilities Accounted for at Fair Value (Details) - Fair Value, Recurring [Member] - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Dec. 31, 2024
Fair Value, Inputs, Level 1 [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Money market funds and other bank deposits $ 587,550 $ 241,558 $ 26,868
Equity securities 178,049 107,486 33,158
Certificates of deposit and other deposits 1,172 1,174 1,177
Fair Value, Inputs, Level 2 [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Receivables from provisional concentrate sales 215,534 170,230 31,515
Foreign exchange contracts 384 1,127 0
Metal forward contracts 16,363 15,840 18,039
Foreign exchange contracts 1,318 829 10,176
Metal forward contracts $ 15,230 $ 38,273 $ 0
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Liabilities Liabilities Liabilities
Fair Value, Inputs, Level 2 [Member] | Gold      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Metal forward contracts $ 3,254 $ 0