Stock-Based Compensation (Summary of the Activity for Stock Option Awards) (Details) (Stock Options [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended
Oct. 28, 2012
Stock Options [Member]
Shares
Beginning balance	3,690
Options granted	213
Options exercised	(660)
Options cancelled/forfeited	(110)
Ending balance	3,133
Exercisable at end of period	2,475
Weighted average exercise price (per share)
Beginning balance	$ 16.94
Options granted	$ 28.17
Options exercised	$ 15.35
Options cancelled/forfeited	$ 25.68
Ending balance	$ 17.73
Exercisable at end of period	$ 16.39
Aggregate intrinsic value
Beginning balance	$ 44,435
Ending balance	23,410
Exercisable at end of period	21,175
Average urecognized compensation
Beginning balance	4,699
Ending balance	$ 4,044
Number Of Shares Exercisable
Beginning balance	2,767
Ending balance	2,475
Weighted average contractual term (years)
Exercisable at end of period	2 years 2 months

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Net number of share options (or share units) granted during the period.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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