Pensions and Other Postretirement Benefits (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Oct. 02, 2011	Oct. 03, 2010	Oct. 02, 2011	Oct. 03, 2010
Retirement Plans [Member]
Components of net periodic benefit cost
Service cost	$ 146	$ 125	$ 433	$ 372
Interest cost	214	198	641	592
Expected return on plan assets	(279)	(251)	(834)	(751)
Amortization of prior service cost/ (credit)	3	1	7	7
Amortization of net transition obligation			1	1
Recognized actuarial losses	97	59	291	176
Net periodic benefit cost	181	132	539	397
Other Benefit Plans [Member]
Components of net periodic benefit cost
Service cost	38	33	112	100
Interest cost	47	52	141	152
Expected return on plan assets			(1)	(1)
Amortization of prior service cost/ (credit)	(1)	(2)	(2)	(4)
Amortization of net transition obligation
Recognized actuarial losses	11	12	34	37
Net periodic benefit cost	$ 95	$ 95	$ 284	$ 284