Pension and Other Benefit Programs - Accumulated Other Comprehensive Loss, Before Tax, not yet Recognized in Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Oct. 01, 2022
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax	$ (541)
Net actuarial loss	2,792
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	2,251
Prepaid Accrued Pension Costs	(2,823)
Net balance sheet liability (asset)	(572)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax	15
Net actuarial loss	2,929
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	2,944
Prepaid Accrued Pension Costs	(3,696)
Net balance sheet liability (asset)	(752)	$ 307
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax	(556)
Net actuarial loss	(137)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	(693)
Prepaid Accrued Pension Costs	873
Net balance sheet liability (asset)	$ 180	$ 790