Share-Based Compensation Cost by Award Type (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 6 Months Ended
Jul. 28, 2012
Jul. 30, 2011
Jul. 28, 2012
Jul. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation $ 5,000 $ 2,607 $ 8,856 $ 4,753
Stock Options [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation 2,159 1,705 4,057 3,129
Restricted Stock Units (RSUs) [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation 2,838 841 4,786 1,480
Restricted Stock [Member]
       
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation $ 3 $ 61 $ 13 $ 144