Retirement Plans (Retirement Expenses) (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Total Retirement Expense	$ 44	$ 77	$ 65
Pension Plan [Member]
Total net periodic benefit cost	(83)	(54)	(64)
Supplemental Employee Retirement Plan
Total net periodic benefit cost	31	41	38
Non qualified defined contribution plan [Member] | Other Postretirement Benefit Plan [Member]
Defined Contribution Plan, Cost Recognized	$ 2	$ 2	$ 2