v3.25.2
Property, plant and equipment (Details) - USD ($)
$ in Thousands
6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Property, plant and equipment    
Additions $ 32,759 $ 28,723
Depreciation on property, plant and equipment 37,882 34,096
Mine development    
Property, plant and equipment    
Additions 14,022 11,318
Construction in progress    
Property, plant and equipment    
Additions $ 18,706 $ 17,149