Share-Based Compensation (Schedule Of Stock Option Activity Under Plan) (Details) - $ / shares	9 Months Ended	12 Months Ended
Oct. 28, 2017	Jan. 28, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Option Maximum Term	10 years
Stock Option Vesting Period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, Balance (shares)	866,637
Options outstanding, Forfeited (shares)	(18,972)
Options outstanding, Exercised (shares)	(138,312)
Options outstanding, Balance (shares)	709,353	866,637
Options outstanding, Exercisable (shares)	564,365,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Weighted average exercise price, Balance (dollars per share)	$ 29,600
Weighted average exercise price, Forfeited (dollars per share)	37,110
Weighted average exercise price, Exercised (dollars per share)	27,450
Weighted average exercise price, Balance (dollars per share)	29,820	$ 29,600
Weighted average exercise price, Exercisable (dollars per share)	$ 28,690
Weighted Average Remaining Contractual Term (in years)	6 years	6 years 8 months 5 days
Weighted average remaining contractual term, Exercisable	5 years 7 months

Stock Option Maximum Term

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Stock Option Vesting Period

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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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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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 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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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 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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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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