Defined contribution and defined benefit retirement plans - Schedule of Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (Details) - Pension Plans - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Pension Plans Postretirement And Other Employee Benefits [Line Items] | |||
| Net actuarial gains (losses) | $ 39.0 | $ 16.0 | $ (25.5) |
| Amortization of unrecognized net actuarial losses | 3.1 | 3.7 | 3.8 |
| Amortization of unrecognized prior service cost (credit) | 0.1 | 0.1 | |
| Settlement loss | 29.0 | 0.4 | 6.5 |
| Total | $ 71.2 | $ 20.2 | $ (15.2) |
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- Definition Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before tax, of reclassification adjustment from accumulated other comprehensive (income) loss for settlements of defined benefit plan. No definition available.
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- Definition Pension plans postretirement and other employee benefits. No definition available.
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- Details
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