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Share-Based Compensation (Restricted Stock Units Assumptions) (Details) - Market-based restricted stock units [Member]
3 Months Ended
Apr. 30, 2016
$ / shares
May. 02, 2015
$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Grant date market price (in dollars per share) $ 31.67 $ 22.46
Fair value (in dollars per share) $ (38.22) $ (19.04)
Price volatility 44.00% 45.00%
Expected term (years) 2 years 9 months 18 days 2 years 9 months 18 days
Risk-free interest rate 1.10% 0.90%
Dividend yield 2.50% 3.50%
Average volatility of peer companies 34.40% 34.00%
Average correlation coefficient of peer companies 0.3382 0.3288