Goodwill and Identified Intangible Assets - Estimated Future Amortization Expense of Purchased Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Apr. 03, 2015	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
2015 (remaining 9 months)	$ 4,595
2016	4,097
Total future amortization expense	8,692us-gaap_FiniteLivedIntangibleAssetsNet	10,599us-gaap_FiniteLivedIntangibleAssetsNet
Product cost of revenue [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
2015 (remaining 9 months)	258
2016	0
Total future amortization expense	258
Operating Expenses [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
2015 (remaining 9 months)	4,337
2016	4,097
Total future amortization expense	$ 8,434

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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 (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ 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 (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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