XML 90 R64.htm IDEA: XBRL DOCUMENT v3.23.2
Fair Value Measurements (Details)
3 Months Ended 6 Months Ended
Jun. 30, 2023
USD ($)
EquityInstruments
Jun. 30, 2023
USD ($)
EquityInstruments
Dec. 31, 2022
USD ($)
Fair value measurements      
Transfer from Level 1 to 2 of financial assets $ 0 $ 0  
Transfer from Level 2 to 1 of financial assets 0 0  
Transfer from Level 1 to 2 of financial liabilities 0 0  
Transfer from Level 2 to 1 of financial liabilities 0 0  
Transfers Into Level 3 of financial assets 0 0  
Transfers Out of Level 3 of financial assets 0 0  
Transfers Into Level 3 of financial liabilities 0 0  
Transfers Out of Level 3 of financial liabilities $ 0 $ 0  
Number of investments with no quoted market price in an active market | EquityInstruments 1 1  
Recurring Basis      
Fair value measurements      
Financial assets, at fair value $ 239,800,000 $ 239,800,000 $ 236,500,000
Recurring Basis | Level 1      
Fair value measurements      
Financial assets, at fair value 225,800,000 225,800,000 220,800,000
Recurring Basis | Level 2      
Fair value measurements      
Financial assets, at fair value 10,100,000 10,100,000 11,900,000
Recurring Basis | Level 3      
Fair value measurements      
Financial assets, at fair value 3,900,000 3,900,000 3,800,000
Receivables from provisional concentrate sales | Recurring Basis      
Fair value measurements      
Financial assets, at fair value 7,500,000 7,500,000 9,300,000
Receivables from provisional concentrate sales | Recurring Basis | Level 2      
Fair value measurements      
Financial assets, at fair value 7,500,000 7,500,000 9,300,000
Equity investments | Recurring Basis      
Fair value measurements      
Financial assets, at fair value 229,700,000 229,700,000 224,600,000
Equity investments | Recurring Basis | Level 1      
Fair value measurements      
Financial assets, at fair value 225,800,000 225,800,000 220,800,000
Equity investments | Recurring Basis | Level 3      
Fair value measurements      
Financial assets, at fair value 3,900,000 3,900,000 3,800,000
Warrants. | Recurring Basis      
Fair value measurements      
Financial assets, at fair value 2,600,000 2,600,000 2,600,000
Warrants. | Recurring Basis | Level 2      
Fair value measurements      
Financial assets, at fair value $ 2,600,000 $ 2,600,000 $ 2,600,000