Pension and Other Benefit Programs - Net Periodic Benefit Cost (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Sep. 29, 2012
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service costs	$ 277	$ 349	$ 278
Interest costs	488	433	440
Expected return on plan assets	(645)	(604)	(514)
Amortization of prior year service costs	14	10	12
Recognized net actuarial loss / (gain)	145	418	309
Net periodic benefit cost	279	606	525
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Service costs	10	18	21
Interest costs	65	66	74
Expected return on plan assets	(36)	(30)	(23)
Amortization of prior year service costs	(2)	(2)	(2)
Recognized net actuarial loss / (gain)	(7)	40	31
Net periodic benefit cost	$ 30	$ 92	$ 101