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Derivative financial instruments - Additional information (Details) - USD ($)
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Disclosure of derivative financial instruments [Line Items]      
Unrealized gain (loss) before tax $ (6,232,000) $ 10,696,000 $ 6,678,000
Hedge ineffectiveness 0 454,000 1,403,000
Effect on settlement of hedging financial instruments 0 818,000 1,547,000
Interest rate hedge      
Disclosure of derivative financial instruments [Line Items]      
Unrealized gain (loss) before tax 644,000 1,991,000  
Effect on settlement of hedging financial instruments 818,000 (1,547,000)  
Unrealized gain (loss) net of tax income 454,000 1,403,000  
Copper and Zinc prices hedge      
Disclosure of derivative financial instruments [Line Items]      
Unrealized gain (loss) before tax 9,047,000 15,171,000 9,472,000
Unrealized gain (loss) net of tax income 6,232,000 10,696,000 6,678,000
Other reserves [member] | Copper and Zinc prices hedge      
Disclosure of derivative financial instruments [Line Items]      
Hedge operations gain loss $ 6,056,000 $ 12,774,000 $ (51,952,000)