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Retirement Plans (Schedule of Plan Asset Allocation) (Details)	Sep. 27, 2020
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	100.00%
Asset allocation, target, equity securities	100.00%
Cash & cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	1.00%
Asset allocation, target, equity securities	0.00%
Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	23.00%
Asset allocation, target, equity securities	23.00%
International equities
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	22.00%
Asset allocation, target, equity securities	23.00%
Core fixed funds
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	33.00%
Asset allocation, target, equity securities	32.00%
High yield
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	3.00%
Asset allocation, target, equity securities	4.00%
Alternative investments
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	8.00%
Asset allocation, target, equity securities	8.00%
Real estate
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	9.00%
Asset allocation, target, equity securities	7.00%
Real return bonds
Defined Benefit Plan Disclosure [Line Items]
Percentage of plan assets, equity securities	1.00%
Asset allocation, target, equity securities	3.00%
Minimum | Cash & cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	0.00%
Minimum | Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	12.00%
Minimum | International equities
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	12.00%
Minimum | Core fixed funds
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	27.00%
Minimum | High yield
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	0.00%
Minimum | Alternative investments
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	0.00%
Minimum | Real estate
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	2.00%
Minimum | Real return bonds
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	0.00%
Maximum | Cash & cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	0.00%
Maximum | Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	32.00%
Maximum | International equities
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	32.00%
Maximum | Core fixed funds
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	37.00%
Maximum | High yield
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	8.00%
Maximum | Alternative investments
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	16.00%
Maximum | Real estate
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	12.00%
Maximum | Real return bonds
Defined Benefit Plan Disclosure [Line Items]
Asset allocation, target, equity securities	8.00%

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- Definition

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 55
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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