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Postretirement Health Care and Life Insurance Benefits (Weighted Average Assumptions Used To Determine Net Periodic Costs For Postretirement Plans) (Details) | 12 Months Ended
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Jan. 28, 2017 | Jan. 30, 2016 | Jan. 31, 2015
Other Postretirement Benefit Plan [Member] |  |  |
Discount rate | 3.14% | 3.55% | 4.50%

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- Definition The interest rate used to adjust for the time value of money. + References 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 + Details
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- Details
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