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Stock-based Compensation - Additional Information (Detail) (USD $)
In Millions, except Share data, unless otherwise specified |
1 Months Ended | 3 Months Ended | 6 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
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Sep. 23, 2010
The 2010 Stock Plan
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Jan. 28, 2012
The 2010 Stock Plan
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Jan. 28, 2012
Employee Stock Option
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Jan. 29, 2011
Employee Stock Option
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Jan. 28, 2012
Employee Stock Option
Year
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Jan. 29, 2011
Employee Stock Option
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Jan. 28, 2012
Employee Stock Option
Minimum
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Jan. 28, 2012
Employee Stock Option
Maximum
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Jan. 28, 2012
Restricted Equity Awards
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Jan. 28, 2012
Service-based Restricted Equity Awards
Year
|
Jan. 28, 2012
Performance-based Restricted Equity Awards
Year
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Jan. 28, 2012
Market-based Restricted Equity Awards
Year
|
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||||||||||
| Aggregate number of share that may be issued under Stock Incentive Plan | 18,000,000 | |||||||||||
| Shares available for future grants under stock incentive plan | 3,600,000 | |||||||||||
| Stock options vesting period | 4 years | 5 years | 4 years | 3 years | 3 years | |||||||
| Stock options, maximum period of expiration | 10 years | |||||||||||
| Total unrecognized compensation costs related to non-vested option | $ 30.5 | $ 30.5 | $ 11.0 | $ 16.2 | $ 3.9 | |||||||
| Weighted-average recognition period for unrecognized compensation cost (years) | 2.8 | 4.2 | 1.9 | 1.8 | ||||||||
| Total intrinsic value of options exercised | 6.8 | 4.1 | 8.5 | 5.2 | ||||||||
| Total fair value of options vested | $ 1.9 | $ 2.0 | $ 9.1 | $ 8.1 | ||||||||
| Share based award description | The 2010 Stock Plan also allows for the issuance of shares of restricted stock and restricted stock units (“RSUs”). Any shares of restricted stock or RSUs are counted against the shares available for future grant limit as three shares for every one restricted share or RSU granted. In general, if options are cancelled for any reason or expire, the shares covered by such options again become available for grant. If a share of restricted stock or an RSU is forfeited for any reason, three shares become available for grant. | |||||||||||
| Number of shares issuable per vesting of one restricted stock or unit | 3 | |||||||||||
| Number of shares available for grant upon forfeiture of a restricted stock or unit | 3 | |||||||||||