Pension and Other Benefit Programs - Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Sep. 28, 2013
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service costs	$ 332	$ 277	$ 349
Interest costs	521	488	433
Expected return on plan assets	(711)	(645)	(604)
Amortization of prior year service costs	16	14	10
Recognized net actuarial loss / (gain)	247	145	418
Net periodic benefit cost	405	279	606
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Service costs	14	10	18
Interest costs	68	65	66
Expected return on plan assets	(39)	(36)	(30)
Amortization of prior year service costs	(1)	(2)	(2)
Recognized net actuarial loss / (gain)	10	(7)	40
Net periodic benefit cost	$ 52	$ 30	$ 92