Benefit Plans (Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 31, 2015	Nov. 01, 2014	Oct. 31, 2015	Nov. 01, 2014
401(k) defined contribution plan expense	$ 22	$ 21	$ 69	$ 71
Total Retirement Expense	19	14	60	51
Pension Plan [Member]
Service cost	2	2	5	5
Interest cost	35	38	103	113
Expected return on assets	(59)	(62)	(176)	(185)
Recognition of net actuarial (gain) loss	9	6	28	19
Amortization of prior service credit	0	0	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	(13)	(16)	(40)	(48)
Supplemental Employee Retirement Plan [Member]
Service cost	0	0	0	0
Interest cost	7	8	23	25
Recognition of net actuarial (gain) loss	3	1	8	3
Amortization of prior service credit	0	0	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	10	9	31	28
Other Postretirement Benefit Plan [Member]
Service cost	0	0	0	0
Interest cost	2	3	6	7
Recognition of net actuarial (gain) loss	0	(2)	0	(4)
Amortization of prior service credit	0	0	0	0
Defined Benefit Plan, Net Periodic Benefit Cost	$ 2	$ 1	$ 6	$ 3