Pension and Other Benefit Programs - Accumulated Other Comprehensive Loss, Before Tax, not yet Recognized in Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	Oct. 01, 2016	Oct. 03, 2015
Defined Benefit Plan Disclosure [Line Items]
Prior service cost	$ (56)
Net actuarial loss	(5,733)
Total amounts included in AOCI	(5,789)
Prepaid / (accrued) pension cost	565
Net balance sheet liability	(5,224)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Prior service cost	(56)
Net actuarial loss	(5,470)
Total amounts included in AOCI	(5,526)
Prepaid / (accrued) pension cost	1,447
Net balance sheet liability	(4,079)	$ (2,964)
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Prior service cost	0
Net actuarial loss	(263)
Total amounts included in AOCI	(263)
Prepaid / (accrued) pension cost	(882)
Net balance sheet liability	$ (1,145)	$ (1,022)