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Pension Benefit Obligations -Schedule of Fair Values of the Defined Benefit Pension Plan and the Postretirement Plan Assets by Major Asset Categories (Details) - USD ($) $ in Millions | Sep. 27, 2024 | Sep. 29, 2023 | Sep. 30, 2022 | Oct. 01, 2021
--- | --- | --- | --- | ---
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |  |
Fair value of plan assets at end of year | $ 315 | $ 281 | $ 271 | $ 366
Quoted Prices in Active Markets (Level 1) |  |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |  |
Fair value of plan assets at end of year | 134 | 218 |  |
Investments measured at NAV |  |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |  |
Fair value of plan assets at end of year | 181 | 63 |  |
Cash and cash equivalents | Quoted Prices in Active Markets (Level 1) |  |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |  |
Fair value of plan assets at end of year | 6 | 9 |  |
Diversified and equity funds | Quoted Prices in Active Markets (Level 1) |  |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |  |
Fair value of plan assets at end of year | 0 | 147 |  |
Diversified and equity funds | Investments measured at NAV |  |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |  |
Fair value of plan assets at end of year | 94 | 0 |  |
Fixed income funds | Quoted Prices in Active Markets (Level 1) |  |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |  |
Fair value of plan assets at end of year | 128 | 62 |  |
Common collective funds - debt | Investments measured at NAV |  |  |  |
Defined Benefit Plan, Plan Assets, Category [Line Items] |  |  |  |
Fair value of plan assets at end of year | $ 87 | $ 63 |  |

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