Employee benefits - Defined benefit plans (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Retirement Benefits [Abstract] | ||
| Net defined benefit liability | $ 29.2 | $ 31.6 |
| Expected future benefit payments, 2026 | 0.8 | |
| Expected future benefit payments, 2027 | 0.7 | |
| Expected future benefit payments, 2028 | 1.3 | |
| Expected future benefit payments, 2029 | 1.6 | |
| Expected future benefit payments, 2030 | 3.3 | |
| Expected future benefit payments, 2031-2035 | $ 13.9 |
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- Definition Defined Benefit Plan, Expected Future Benefit Payment, After Year Four For Next Five Years No definition available.
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- References No definition available.
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- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension plan. Excludes other postretirement benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of benefit for defined benefit plan expected to be paid in remainder of current fiscal year. No definition available.
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- Definition Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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