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Retirement Plans - Fair Value of Plan Assets by Main Asset Category (Details) - USD ($) $ in Thousands | Sep. 28, 2025 | Sep. 29, 2024
--- | --- | ---
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Fair value of plan assets | $ 43,553 | $ 46,815
Equities |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Fair value of plan assets | 692 | 3,739
Mutual funds |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Fair value of plan assets | 23,750 | 22,923
Liability driven investment funds |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Fair value of plan assets | 15,607 | 15,833
Bonds |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Fair value of plan assets | 2,647 | 2,657
Cash/other |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |
Fair value of plan assets | $ 857 | $ 1,663

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