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Retirement Plans - Narrative (Details)	3 Months Ended		4 Months Ended	9 Months Ended
	Jul. 05, 2020 USD ($)	Apr. 12, 2020 USD ($)	Jan. 19, 2020 USD ($)	Jul. 04, 2021 healthcare_plan defined_benefit_plan	Jan. 01, 2020 USD ($)
Retirement Benefits [Abstract]
Number of sponsored defined benefit pension plans | defined_benefit_plan				2
Lump sum payments from Qualified Plan			$ 122,300,000
Pension settlement	$ (100,000)	$ (300,000)	$ (38,600,000)
Number of postretirement health care plans | healthcare_plan				2
Minimum required contribution for retirement plans					$ 0

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Minimum required contribution for retirement plans

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- Definition

Number Of Defined Benefit Pension Plans Sponsored

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Postretirement Medical Plan, Number Sponsored

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(7)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 45
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=109237824&loc=SL108413299-114919

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)(7)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920

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Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(8)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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