Stock-Based Compensation (Summary of the Activity for Stock Option Awards) (Details) (Stock Option Awards [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
Jul. 29, 2012 Y
Stock Option Awards [Member]
Shares
Beginning balance	3,690
Options granted	206
Options exercised	(343)
Options cancelled/forfeited	(107)
Ending balance	3,446
Exercisable at end of the period	2,643
Weighted average exercise price (per share)
Beginning balance	$ 16.94
Options granted	$ 28.29
Options exercised	$ 16.23
Options cancelled/forfeited	$ 26.06
Ending balance	$ 17.40
Exercisable at end of the period	$ 16.17
Aggregate Intrinsic Value
Beginning balance	$ 44,435
Ending balance	25,057
Exercisable at end of the period	21,792
Aggregate Unrecognized Compensation
Beginning balance	4,699
Ending balance	$ 4,635
Number of Shares Exercisable
Beginning balance	2,767
Ending balance	2,643
Weighted Average Contractual Term (years)
Exercisable at end of the period (years)	2.3

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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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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance sheet date.

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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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The weighted average period between the balance sheet date and expiration for all vested portions of options outstanding and currently exercisable (or convertible) under the plan, which may be expressed in a decimal value for number of years.

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The weighted average price at which option holders acquired shares when converting their stock options into shares under the plan during the reporting period.

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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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The weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated during the reporting period due to noncompliance with plan terms during the reporting period.

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

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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 stock options awarded under the plan during the reporting period.

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date.

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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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The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

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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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Number of share options (or share units) exercised during the current period.

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