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Pension Benefit Obligations - Narrative (Details) - USD ($) $ in Millions | 12 Months Ended
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Sep. 27, 2024 | Sep. 29, 2023 | Sep. 30, 2022
Retirement Benefits [Abstract] |  |  |
Gain (loss) corridor rate | 10.00% |  |
Pension adjustments | $ 9 | $ 24 | $ 8
Applicable amount of deferred income taxes included in other comprehensive income | $ 3 | $ 6 | $ 2
Expected long-term rate of return on plan assets | 7.00% | 7.00% | 6.50%
Percentage of personnel covered by collective-bargaining agreements | 24.00% |  |
Percentage of personnel covered by collective-bargaining agreements expire in one year | 10.00% |  |

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