v2.4.0.6
Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
6 Months Ended
Jan. 28, 2012
Jan. 29, 2011
Jul. 30, 2011
Significant Accounting Policies [Line Items]      
Unrecognized tax benefits (including accrued interest and penalties) $ 14.4   $ 21.9
Estimated decrease in unrecognized tax benefits, over the next twelve months $ (7.1)    
Anti-dilutive options and/or contingent vesting of performance-based and market-based restricted stock units that were excluded from diluted share calculations 2.2 2.1