Stock Options Outstanding and Exercisable (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Apr. 28, 2012 Year	Jan. 28, 2012
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower limit	$ 9.85
Range of Exercise Prices, Upper limit	$ 30.92
Options Outstanding, Number of Shares	7,307	7,227
Options Outstanding, Weighted-Average Remaining Contractual Life	6.33
Options Outstanding, Weighted-Average Exercise Price	$ 20.11	$ 18.44
Options Exercisable, Number of Shares	4,838
Options Exercisable, Weighted-Average Exercise Price	$ 18.83
$9.85 to $15.10
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower limit	$ 9.85
Range of Exercise Prices, Upper limit	$ 15.10
Options Outstanding, Number of Shares	2,576
Options Outstanding, Weighted-Average Remaining Contractual Life	6.75
Options Outstanding, Weighted-Average Exercise Price	$ 12.41
Options Exercisable, Number of Shares	2,076
Options Exercisable, Weighted-Average Exercise Price	$ 12.01
$15.74 to $23.42
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower limit	$ 15.74
Range of Exercise Prices, Upper limit	$ 23.42
Options Outstanding, Number of Shares	2,024
Options Outstanding, Weighted-Average Remaining Contractual Life	7.43
Options Outstanding, Weighted-Average Exercise Price	$ 20.01
Options Exercisable, Number of Shares	1,059
Options Exercisable, Weighted-Average Exercise Price	$ 21.05
$23.59 to $28.16
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower limit	$ 23.59
Range of Exercise Prices, Upper limit	$ 28.16
Options Outstanding, Number of Shares	1,778
Options Outstanding, Weighted-Average Remaining Contractual Life	2.61
Options Outstanding, Weighted-Average Exercise Price	$ 25.72
Options Exercisable, Number of Shares	1,703
Options Exercisable, Weighted-Average Exercise Price	$ 25.76
$30.92 to $30.92
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower limit	$ 30.92
Range of Exercise Prices, Upper limit	$ 30.92
Options Outstanding, Number of Shares	929
Options Outstanding, Weighted-Average Remaining Contractual Life	9.90
Options Outstanding, Weighted-Average Exercise Price	$ 30.92

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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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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.

+ References

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-Number 123R

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- Definition

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.

+ References

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(a)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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-Number 123R

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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