v3.25.2
Fair value measurement - Silver stream embedded derivative, key inputs were used (Details)
6 Months Ended 12 Months Ended
Jun. 30, 2025
USD ($)
Dec. 31, 2024
USD ($)
Fair value measurement    
Percentage of assets 5.00%  
Percentage of possible decrease in unobservable assets 5.00%  
Silver stream embedded derivative | Spot price    
Fair value measurement    
Significant unobservable input, asset 36.11 28.91
Percentage of liabilities 5.00%  
Percentage of assets 5.00%  
Increase in fair value measurement liabilities $ 5,304,000 $ 4,421,000
Percentage of possible decrease in unobservable liabilities 5.00%  
Percentage of possible decrease in unobservable assets 5.00%  
Decrease in fair value measurement liabilities $ 5,304,000 $ 4,421,000
Silver stream embedded derivative | Own credit spread    
Fair value measurement    
Significant unobservable input, asset 8.32 7.99