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Retirement Plans (Narrative) (Details) |  | 4 Months Ended | 8 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jan. 01, 2016 | Jan. 19, 2020 USD ($) | Sep. 27, 2020 USD ($) | Oct. 03, 2021 USD ($) defined_benefit_plan | Sep. 27, 2020 USD ($) | Sep. 29, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Number of sponsored defined benefit pension plans | defined_benefit_plan |  |  |  | 2 |  |
Lump sum payments from qualified plan |  | $ 122,300,000 |  |  |  |
Pension settlement |  | $ 38,600,000 | $ 600,000 |  |  |
Minimum required contribution for retirement plans |  |  |  | $ 0 |  |
Qualified Defined Contribution Plan |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Minimum age of eligible employees |  |  |  | 21 years |  |
Employer matching contribution, percent of match | 100.00% |  |  |  |  |
Employer matching contribution, percent of employees' gross pay | 4.00% |  |  |  |  |
Defined contribution plan, Company contributions |  |  |  | $ 1,600,000 | $ 1,600,000 | $ 1,700,000
Non-Qualified Deferred Compensation Plan |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |
Defined contribution plan, Company contributions |  |  |  | $ 100,000 | $ 300,000 | $ 200,000
Maximum annual contributions per employee, percent |  |  |  | 50.00% |  |
Maximum annual contributions per employee, percent of bonus |  |  |  | 85.00% |  |

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- Definition Defined contribution plan, minimum age of eligible employees. + References No definition available. + Details
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- Definition Minimum required contribution for retirement plans + References No definition available. + Details
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- Definition Number Of Defined Benefit Pension Plans Sponsored + References No definition available. + Details
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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 + Details
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- Definition 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 + Details
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