Fair value measurement - Schedule of Fair Value of Pension Plan Assets by Level within Fair Value Hierarchy (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	$ 337,902
Retirement Plans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	337,902	$ 386,108	$ 385,005
Retirement Plans | Cash and other | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	81	87
Retirement Plans | Cash and other | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	0	0
Retirement Plans | Cash and other | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	0	0
Retirement Plans | Cash and other | Fair Value, Inputs, Level 1, 2 and 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	81	87
Retirement Plans | Common collective trust - equities | Fair Value, Inputs, Level 1, 2 and 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	68,146	67,314
Retirement Plans | Common collective trust - fixed income | Fair Value, Inputs, Level 1, 2 and 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	269,665	318,594
Retirement Plans | Partnership/joint venture interests | Fair Value, Inputs, Level 1, 2 and 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value of plan assets	$ 10	$ 113