v3.25.2
Balance Sheet and Cash Flow Supplemental Information - Schedule of Additional Supplemental Cash Flow Information (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Dec. 31, 2024
Supplemental non cash information:        
Operating activities - Chloride slag inventory purchases made from AMIC (including VAT)   $ 11 $ 34  
Operating activities - MGT sales made to AMIC   3 3  
Operating activities - Withholding tax on sale of royalty interest $ 7 0 7  
Investing activities - Proceeds from sale of royalty interest   0 7  
Investing activities - In-kind receipt of AMIC loan repayment   11 34  
Financing activities - Initial commercial insurance premium financing agreement   1 0  
Financing activities - Repayment of MGT loan   3 3  
Capital expenditures acquired but not yet paid   55   $ 91
Condensed Balance Sheet Statements, Captions [Line Items]        
Investing activities - Proceeds from sale of royalty interest   0 7  
Operating activities - Withholding tax on sale of royalty interest 7 $ 0 $ 7  
CANADA        
Supplemental non cash information:        
Investing activities - Proceeds from sale of royalty interest 28      
Condensed Balance Sheet Statements, Captions [Line Items]        
Investing activities - Proceeds from sale of royalty interest $ 28