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Stock-Based Compensation (Summary of Fair Value Assumptions) (Details) (USD $)
3 Months Ended 6 Months Ended
Jul. 29, 2012
Jul. 31, 2011
Jul. 29, 2012
Jul. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Estimated volatility 40.00% 41.00%    
Estimated volatility rate, minimum     40.00% 40.00%
Estimated volatility rate, maximum     41.00% 41.00%
Dividend yield 0.00% 0.00% 0.00% 0.00%
Risk-free interest rate 0.70%   0.70%  
Risk-free interest rate, minimum   1.60%   1.60%
Risk free interest rate, maximum   1.65%   1.80%
Weighted average fair value on grant date $ 8.31 $ 10.09 $ 9.68 $ 8.54
Minimum [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected lives, in years 4.4 4.4 4.4 4.4
Maximum [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected lives, in years 4.6 4.7 4.6 4.7