Fair Value Disclosures (Other Financial Instruments) (Details) - USD ($)
$ in Millions
Oct. 31, 2015
Jan. 31, 2015
Nov. 01, 2014
Fair Value Disclosures [Abstract]      
Long-term debt, excluding unamortized debt issuance costs, including current maturities, Fair Value $ 4,947 $ 4,834 $ 4,910
Long-term debt, excluding unamortized debt issuance costs, including current maturities, carrying amount 5,329 $ 5,350 $ 5,357
Fair Value, Inputs, Level 2 [Member]      
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]      
Derivative Liability $ 21