Pension and Other Benefit Programs - Accumulated Other Comprehensive Loss, Before Tax, not yet Recognized in Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	Oct. 02, 2021	Oct. 03, 2020
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax	$ 18
Net actuarial loss	6,961
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	6,979
Prepaid Accrued Pension Costs	(2,868)
Net balance sheet liability	4,111
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax	18
Net actuarial loss	6,628
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	6,646
Prepaid Accrued Pension Costs	(3,767)
Net balance sheet liability	2,879	$ 5,162
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, Prior Service Cost (Credit), before Tax	0
Net actuarial loss	333
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax	333
Prepaid Accrued Pension Costs	899
Net balance sheet liability	$ 1,232	$ 1,333