Benefit Plans (Net Periodic Benefit Cost) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 28, 2012	Jul. 30, 2011	Jul. 28, 2012	Jul. 30, 2011
Pension Contributions				$ 225
Pension Plan [Member]
Service cost	30	25	58	51
Interest cost	39	40	78	80
Expected return on assets	(63)	(62)	(126)	(124)
Amortization of net actuarial (gain) loss	36	23	71	44
Amortization of prior service credit	0	0	0	0
Total net periodic benefit cost	42	26	81	51
Supplemental Employee Retirement Plans, Defined Benefit [Member]
Service cost	1	2	3	3
Interest cost	9	9	17	18
Amortization of net actuarial (gain) loss	5	2	9	4
Amortization of prior service credit	0	(1)	0	(1)
Total net periodic benefit cost	15	12	29	24
Amount Recognized In Net Periodic Postretirement Benefit Cost [Member] | Other Postretirement Benefit Plans, Defined Benefit [Member]
Service cost	0	0	0	0
Interest cost	3	3	6	7
Amortization of net actuarial (gain) loss	(1)	(2)	(2)	(3)
Amortization of prior service credit	0	0	0	0
Total net periodic benefit cost	$ 2	$ 1	$ 4	$ 4