Benefit Plans (Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 29, 2017	Apr. 30, 2016
Total Retirement Expense	$ 9	$ 13
Settlement charges	0	13
Pension Plan [Member]
Service cost	1	1
Interest cost	27	28
Expected return on assets	(56)	(56)
Recognition of net actuarial (gain) loss	8	8
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	(20)	(19)
Supplemental Employee Retirement Plan [Member]
Service cost	0	0
Interest cost	6	6
Recognition of net actuarial (gain) loss	2	2
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	8	8
Other Postretirement Benefit Plan [Member]
Service cost	0	0
Interest cost	1	2
Recognition of net actuarial (gain) loss	(1)	(1)
Amortization of prior service credit	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	0	1
Defined Contribution Qualified Plan [Member]
Defined contribution plans expense	21	24
Non qualified defined contribution plan [Member]
Defined contribution plans expense	$ 0	$ 0