v3.26.1
Asset retirement obligations - Schedule of Rollforward Analysis (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]        
Balance as of January 1     $ 294  
Accretion expense $ 3 $ 4 7 $ 7
Liabilities settled     (6)  
Foreign currency translation adjustment     (5)  
Balance as of June 30 $ 290   $ 290