Retirement Benefits (Estimated future benefit payments) (Details) $ in Thousands	Dec. 27, 2024 USD ($)
Pension Benefits
Estimated future benefit payments
2025	$ 6,148
2026	8,297
2027	10,028
2028	10,093
2029	11,463
Years 2030-2034	65,071
Postretirement Medical Benefits
Estimated future benefit payments
2025	1,633
2026	1,574
2027	1,580
2028	1,561
2029	1,543
Years 2030-2034	$ 7,484

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- Definition

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 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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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 fifth 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 benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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