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Stock-Based Compensation - Summary of Fair Value Assumptions (Details) (USD $)
3 Months Ended
Apr. 27, 2014
Apr. 28, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Estimated volatility, minimum 33.00% 34.00%
Estimated volatility, maximum 34.00% 35.00%
Dividend yield 0.00% 0.00%
Risk-free interest rate, minimum 1.26% 0.65%
Risk-free interest rate, maximum 1.31% 0.69%
Weighted average fair value on grant date $ 7.22 $ 9.04
Minimum [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected lives 3 years 4 years 2 months
Maximum [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected lives 4 years 5 months 4 years 8 months