Retirement Benefits - Schedule of Expected Benefit Payments (Details) $ in Millions	Dec. 28, 2025 USD ($)
Pension Benefits
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2026	$ 16.4
2027	17.8
2028	18.7
2029	19.3
2030	20.2
2031-2035	113.1
Other Postretirement Benefits
Defined Benefit Plan Expected Future Benefit Payments [Abstract]
2026	23.7
2027	22.3
2028	20.8
2029	19.4
2030	17.8
2031-2035	69.0
Medicare Part D Subsidy
2026	0.0
2027	0.0
2028	0.0
2029	0.0
2030	0.0
2031-2035	$ 0.0

Defined Benefit Plan Expected Future Benefit Payments [Abstract]

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Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-5

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of prescription drug subsidy receipt expected after fifth fiscal year following current fiscal year.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480266/715-60-50-4

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