Benefit Plans (Net Periodic Benefit Cost) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	May 03, 2014	May 04, 2013
Defined contribution plan, periodic cost recognized	$ 25	$ 5
Pension Plan [Member]
Service cost	2	28
Interest cost	38	36
Expected return on assets	(61)	(60)
Recognition of net actuarial (gain) loss	6	35
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	(15)	39
Supplemental Employee Retirement Plans, Defined Benefit [Member]
Service cost	0	2
Interest cost	8	8
Recognition of net actuarial (gain) loss	1	4
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	9	14
Other Postretirement Benefit Plans, Defined Benefit [Member]
Service cost	0	0
Interest cost	2	3
Recognition of net actuarial (gain) loss	(1)	(1)
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	$ 1	$ 2