Postretirement Benefits (Amounts Recognized As Liabilities In The Consolidated Balance Sheets) (Details) - USD ($) $ in Millions	Jan. 28, 2017	Jan. 30, 2016
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Accrued salaries, wages and related benefits	$ 8	$ 8
Other noncurrent liabilities	180	173
Net amount recognized	$ 188	$ 181