Interest Expense on Convertible Senior Notes (Detail) $ in Thousands	9 Months Ended
Sep. 28, 2014 USD ($)
Debt Instrument
Contractual interest expense on the coupon	$ 1,757
Amortization of the discount component and debt issuance fees recognized as interest expense	4,493
Total interest expense on the convertible debt	$ 6,250

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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