Postretirement benefits (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
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| Net periodic benefit income | ||||
| Expected return on plan assets | $ 2.4 | $ 2.1 | $ 4.9 | $ 4.3 |
| Amortization of prior service credit | 0.4 | 0.4 | 0.7 | 0.7 |
| Interest cost | (0.3) | (0.4) | (0.6) | (0.8) |
| Amortization of net actuarial losses | 0.0 | (0.2) | (0.1) | (0.4) |
| Net periodic benefit income | $ 2.5 | $ 1.9 | $ 4.9 | $ 3.8 |
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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