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Retirement Plans (Fair Values of Qualified Plan's Assets) (Details) - USD ($) $ in Thousands | Sep. 28, 2025 | Sep. 29, 2024
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 290,569 | $ 302,439
Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 5,793 | 2,933
Global equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 35,961 | 40,193
Liability-hedging assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 190,685 | 200,675
Alternative Investments Member |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 31,629 | 32,100
Real assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 26,501 | 26,538
Fair Value Measured at Net Asset Value Per Share |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 181,202 | 184,920
Fair Value Measured at Net Asset Value Per Share | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Fair Value Measured at Net Asset Value Per Share | Global equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 35,961 | 40,193
Fair Value Measured at Net Asset Value Per Share | Liability-hedging assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 87,111 | 86,089
Fair Value Measured at Net Asset Value Per Share | Alternative Investments Member |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 31,629 | 32,100
Fair Value Measured at Net Asset Value Per Share | Real assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 26,501 | 26,538
Quoted Prices in Active Markets for Identical (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Quoted Prices in Active Markets for Identical (Level 1) | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Quoted Prices in Active Markets for Identical (Level 1) | Global equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Quoted Prices in Active Markets for Identical (Level 1) | Liability-hedging assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Quoted Prices in Active Markets for Identical (Level 1) | Alternative Investments Member |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Quoted Prices in Active Markets for Identical (Level 1) | Real assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 109,367 | 117,519
Significant Other Observable Inputs (Level 2) | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 5,793 | 2,933
Significant Other Observable Inputs (Level 2) | Global equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Other Observable Inputs (Level 2) | Liability-hedging assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 103,574 | 114,586
Significant Other Observable Inputs (Level 2) | Alternative Investments Member |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Other Observable Inputs (Level 2) | Real assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Unobservable Inputs (Level 3) | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Unobservable Inputs (Level 3) | Global equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Unobservable Inputs (Level 3) | Liability-hedging assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Unobservable Inputs (Level 3) | Alternative Investments Member |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Significant Unobservable Inputs (Level 3) | Real assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 0 | $ 0

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