Employee benefit plans - Components of Net Periodic Defined Benefit Cost (Income) (Details) - Defined Benefit Pension Plans - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Defined Benefit Plan Disclosure [Line Items] | ||||
| Interest cost | $ 356 | $ 365 | $ 712 | $ 730 |
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax |
| Expected return on plan assets | $ (317) | $ (335) | $ (634) | $ (670) |
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax |
| Recognized actuarial losses | $ 284 | $ 333 | $ 568 | $ 666 |
| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax | Other Comprehensive Income Loss Amortization Adjustment From A O C I Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax |
| Total | $ 323 | $ 363 | $ 646 | $ 726 |