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Income Taxes - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 6 Months Ended
Jul. 28, 2012
Jul. 30, 2011
Jul. 28, 2012
Jul. 30, 2011
Jan. 28, 2012
Income Taxes [Line Items]          
Net unrecognized tax benefits $ 119.5 $ 126.3 $ 119.5 $ 126.3 $ 116.6
Effective income tax rate 38.30% 37.70% 38.40% 37.90%  
Accrued amounts for interest and penalties 35.1 37.6 35.1 37.6 33.0
Possible decrease in unrecognized tax benefits that would reduce the provision for taxes on earnings, minimum 1.0   1.0    
Possible decrease in unrecognized tax benefits that would reduce the provision for taxes on earnings, maximum $ 50.0   $ 50.0