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Fair Value Measurements (Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands | Sep. 27, 2020 | Sep. 29, 2019
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total liabilities at fair value |  | $ 25,071 | $ 30,104
Quoted Prices in Active Markets for Identical (Level 1) |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total liabilities at fair value | [1] | 25,071 | 30,104
Significant Other Observable Inputs (Level 2) |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total liabilities at fair value | [1] | 0 | 0
Significant Unobservable Inputs (Level 3) |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total liabilities at fair value | [1] | 0 | 0
Non-qualified Deferred Compensation Plan |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total liabilities at fair value |  | 25,071 | 30,104
Non-qualified Deferred Compensation Plan | Quoted Prices in Active Markets for Identical (Level 1) |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total liabilities at fair value |  | 25,071 | 30,104
Non-qualified Deferred Compensation Plan | Significant Other Observable Inputs (Level 2) |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total liabilities at fair value |  | 0 | 0
Non-qualified Deferred Compensation Plan | Significant Unobservable Inputs (Level 3) |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |
Total liabilities at fair value |  | $ 0 | $ 0
[1] | We did not have any transfers in or out of Level 1, 2, or 3

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