Postretirement Health Care and Life Insurance Benefits (Weighted Average Assumptions Used To Determine Projected Benefit Obligations For Postretirement Obligations) (Details)	Jan. 28, 2017	Jan. 30, 2016
Other Postretirement Benefit Plan [Member]
Discount rate	3.99%	4.15%

The interest rate used to adjust for the time value of money for the plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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Period Type:	instant