v3.26.1
Financial Instruments and Other Guarantees (Details)
$ in Millions, $ in Millions
Jun. 30, 2026
USD ($)
Jun. 30, 2026
AUD ($)
Dec. 31, 2025
USD ($)
Dec. 31, 2025
AUD ($)
Guarantee Obligations [Line Items]        
Restricted Cash $ 400.7   $ 709.2  
Restricted cash and collateral 459.8   844.1  
Surety Trust Account        
Guarantee Obligations [Line Items]        
Restricted Cash 309.4   383.6  
Deposits with Regulatory Authorities        
Guarantee Obligations [Line Items]        
Deposits Assets 59.1 $ 86.0 134.9 $ 201.0
Cash backed bank guarantees        
Guarantee Obligations [Line Items]        
Restricted Cash   $ 17.0   $ 312.0
Collateralized letters of credit funding        
Guarantee Obligations [Line Items]        
Restricted Cash 91.3   $ 325.6  
Asset Retirement Obligations        
Guarantee Obligations [Line Items]        
Surety bonds amount 1,194.0      
Letters of credit outstanding, amount 62.3      
Surety Bonds and Letters of Credit Outstanding for Reclamation Support 1,256.3      
Less: Letters of Credit in Support of Surety Bonds 62.3      
Total Obligations Supported, Net 1,194.0      
Asset Retirement and Other Obligations        
Guarantee Obligations [Line Items]        
Surety bonds amount 1,276.4      
Letters of credit outstanding, amount 120.2      
Total Surety Bonds and Letters of Credit Outstanding 1,396.6      
Total Letters of Credit in Support of Surety Bonds (64.2)      
Total Obligations Supported, Net 1,332.4      
Other Obligations        
Guarantee Obligations [Line Items]        
Surety bonds amount 82.4      
Letters of credit outstanding, amount 57.9      
Surety Bonds and Letters of Credit Outstanding for Other Support 140.3      
Less: Letters of Credit in Support of Surety Bonds 1.9      
Total Obligations Supported, Net 138.4      
Accounts Receivable Securitization Program        
Guarantee Obligations [Line Items]        
Letters of credit outstanding, amount 62.0      
Letter of Credit        
Guarantee Obligations [Line Items]        
Letters of credit outstanding, amount 58.2      
Collateralized Letter of Credit Agreement        
Guarantee Obligations [Line Items]        
Letters of credit outstanding, amount $ 77.9