v3.25.2
Commitments and contingencies - Changes in Accrued Environmental Remediation and Related Costs (Details) - USD ($)
$ in Thousands
6 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Commitments and contingencies.    
Balance at the beginning of the period $ 69,278  
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration] Current liability, Noncurrent liability  
Additions charged to expense, net $ 1,479  
Payments, net (57,456)  
Balance at the end of the period $ 13,301  
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration] Current liability, Noncurrent liability  
Amounts recognized in the Condensed Consolidated Balance Sheet at the end of the period:    
Current liability $ 2,706 $ 58,135
Noncurrent liability $ 10,595 $ 11,143