Pensions and Other Postretirement Benefits (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 01, 2012	Apr. 03, 2011
Retirement Plans [Member]
Components of net periodic benefit cost
Service cost	$ 161	$ 143
Interest cost	222	213
Expected return on plan assets	(312)	(278)
Amortization of prior service cost/ (credit)	2	3
Recognized actuarial losses	124	96
Cutailments and Settlements	(1)	0
Net periodic benefit cost	196	177
Other Benefit Plans [Member]
Components of net periodic benefit cost
Service cost	44	37
Interest cost	41	48
Expected return on plan assets	(1)	0
Amortization of prior service cost/ (credit)	(1)	(1)
Recognized actuarial losses	18	11
Cutailments and Settlements	0	0
Net periodic benefit cost	$ 101	$ 95