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Postretirement Health Care and Life Insurance Benefits (Assumed Health Care Cost Trend Rates) (Details)
12 Months Ended
Feb. 03, 2018
Rate
Jan. 28, 2017
Rate
Rates to which is the cost trend rate is assumed to decline (the ultimate trend rate) 4.50% 5.00%
Year that the rate reaches the ultimate trend rate 2027 2027
Minimum [Member]    
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year 5.50% 6.15%
Maximum [Member]    
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year 10.50% 9.75%