Price Range Analysis - Exercisable [Abstract]

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Price Range Analysis - Outstanding [Abstract]

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The ceiling 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.

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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Stock-Based Compensation - Summarized Information of Stock Options Outstanding (Details) - $ / shares shares in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 25, 2015	Jan. 26, 2014	Jan. 27, 2013
Price Range Analysis - Outstanding
Number of shares	1,507
Weighted average exercise price (in dollars per share)	$ 25.18
Weighted average contractual term	3 years 6 months
Price Range Analysis - Exercisable
Number of Shares	775	986	1,275	1,937
Weighted Average Exercise Price (in dollars per share)	$ 25.49
Weighted Average Contractual Term	2 years 4 months
$1.15 - $4.53
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range - lower range limit (in dollars per share)	$ 1.15
Exercise price range - upper range limit (in dollars per share)	$ 4.53
Price Range Analysis - Outstanding
Number of shares	3
Weighted average exercise price (in dollars per share)	$ 4.50
Weighted average contractual term	1 year 7 months
Price Range Analysis - Exercisable
Number of Shares	3
Weighted Average Exercise Price (in dollars per share)	$ 4.50
Weighted Average Contractual Term	1 year 7 months
$7.97 - $13.76
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range - lower range limit (in dollars per share)	$ 7.97
Exercise price range - upper range limit (in dollars per share)	$ 13.76
Price Range Analysis - Outstanding
Number of shares	2
Weighted average exercise price (in dollars per share)	$ 11.19
Weighted average contractual term	4 years
Price Range Analysis - Exercisable
Number of Shares	2
Weighted Average Exercise Price (in dollars per share)	$ 11.19
Weighted Average Contractual Term	4 years
$15.92 - $24.46
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range - lower range limit (in dollars per share)	$ 15.92
Exercise price range - upper range limit (in dollars per share)	$ 24.46
Price Range Analysis - Outstanding
Number of shares	597
Weighted average exercise price (in dollars per share)	$ 20.41
Weighted average contractual term	3 years 5 months
Price Range Analysis - Exercisable
Number of Shares	316
Weighted Average Exercise Price (in dollars per share)	$ 21.18
Weighted Average Contractual Term	1 year 8 months
$24.74 - $35.17
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range - lower range limit (in dollars per share)	$ 24.74
Exercise price range - upper range limit (in dollars per share)	$ 35.17
Price Range Analysis - Outstanding
Number of shares	905
Weighted average exercise price (in dollars per share)	$ 28.44
Weighted average contractual term	3 years 6 months
Price Range Analysis - Exercisable
Number of Shares	454
Weighted Average Exercise Price (in dollars per share)	$ 28.73
Weighted Average Contractual Term	2 years 10 months