Components of Net Periodic Benefit Cost (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 69	$ 73	$ 208	$ 220
Interest cost	111	104	330	311
Expected return on plan assets	(128)	(111)	(385)	(331)
Amortization of prior year service costs	3	3	10	10
Recognized net actuarial loss	77	57	232	171
Net periodic benefit cost	132	126	395	381
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	5	4	16	14
Interest cost	19	17	56	50
Expected return on plan assets	(5)	(6)	(17)	(18)
Amortization of prior year service costs			(1)	(1)
Recognized net actuarial loss	7	2	23	6
Net periodic benefit cost	$ 26	$ 17	$ 77	$ 51