Goodwill and Intangible Assets - Schedule of Indefinite-lived Intangible Assets (Details) - In-process research and development - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2016	Jan. 25, 2015
Indefinite-lived Intangible Assets [Roll Forward]
Beginning balance, gross carrying amount, indefinite-lived intangible assets	$ 4,000	$ 4,000
In-process research and development through acquisitions	0	0
In-process research and development impairment	0	0
Transfers to core technologies	(4,000)	0
Ending balance, gross carrying amount, indefinite-lived intangible assets	$ 0	$ 4,000

Indefinite-lived Intangible Assets, Period Decrease due to Transfer to Finite-lived Intangible Assets

No definition available.

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- Definition

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275

+ Details

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, resulting from a business combination.

+ References

No definition available.

+ Details

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- Details

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