Benefit Plans (Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 30, 2016	May. 02, 2015
401(k) defined contribution plan expense	$ 24	$ 23
Total Retirement Expense	13	21
Settlement charges	13	0
Pension Plan [Member]
Service cost	1	2
Interest cost	28	34
Expected return on assets	(56)	(59)
Recognition of net actuarial (gain) loss	8	10
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	(19)	(13)
Supplemental Employee Retirement Plan [Member]
Service cost	0	0
Interest cost	6	8
Recognition of net actuarial (gain) loss	2	3
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	8	11
Other Postretirement Benefit Plan [Member]
Service cost	0	0
Interest cost	2	2
Recognition of net actuarial (gain) loss	(1)	0
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	$ 1	$ 2