Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2016	Jan. 02, 2016
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service costs	$ 91	$ 80
Interest costs	112	115
Expected return on plan assets	(219)	(188)
Amortization of prior-year service costs	3	3
Recognized net actuarial loss	101	61
Net periodic benefit cost	88	71
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Service costs	3	3
Interest costs	14	15
Expected return on plan assets	(12)	(11)
Amortization of prior-year service costs	0	0
Recognized net actuarial loss	4	2
Net periodic benefit cost	$ 9	$ 9