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Fair Value Measurements - Additional information (Detail) (Fair Value, Inputs, Level 1, USD $)
In Millions, unless otherwise specified
Jul. 28, 2012
Jan. 28, 2012
Fair Value, Inputs, Level 1
   
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Estimated fair value of debt $ 1,586 $ 1,542