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Retirement Plans (Narrative) (Details) - USD ($) |  | 12 Months Ended
--- | --- | ---
Jan. 01, 2016 | Sep. 29, 2019 | Sep. 30, 2018 | Oct. 01, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Decrease in earnings before income taxes due to quarter percentage point decrease in discount rate |  | $ 500,000 |  |
Decrease in earnings before income taxes due to quarter percentage point decrease in long-term rate of return |  | 1,100,000 |  |
Minimum required contribution for retirement plans |  | $ 0 |  |
Qualified Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Estimated participation rate in limited lump sum payment program for terminated employees |  | 40.00% |  |
Reduction in Company's PBO from limited lump sum payment program for terminated employees |  | $ 25,600,000 |  |
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 |  | $ 1,700,000 | $ 2,200,000 | $ 1,900,000
Non-Qualified Deferred Compensation Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Employer matching contribution, percent of employees' gross pay |  | 4.00% |  |
Defined contribution plan, Company contributions |  | $ 200,000 | $ 200,000 | $ 500,000
Maximum annual contributions per employee, percent |  | 50.00% |  |
Maximum annual contributions per employee, percent of bonus |  | 85.00% |  |
Period of years in executive position |  | 10 years |  |

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- Definition Defined benefit plan effect of quarter percentage point decrease in discount rate on earnings before tax. + References No definition available. + Details
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- Definition Defined benefit plan effect of quarter percentage point decrease in long term rate of return on earnings before tax. + References No definition available. + Details
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- Definition Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent of Bonus + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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