Stockholders' Equity (Schedule of Reclassifications out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 01, 2018	Apr. 02, 2017
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Net revenue	$ 344,973	$ 323,657
Cost of revenue	240,468	226,725
Research and development	28,947	22,683
Sales and marketing	43,658	38,229
General and administrative	16,638	13,194
Tax impact	460	(553)
Amount reclassified from accumulated other comprehensive income, Net of tax	(1,732)	1,027
Gain (losses) on cash flow hedge
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	(2,192)	1,580
Amount Reclassified from AOCI \| Gain (losses) on cash flow hedge
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Total before tax	(2,192)	1,580
Tax impact	460	(553)
Amount reclassified from accumulated other comprehensive income, Net of tax	(1,732)	1,027
Amount Reclassified from AOCI \| Gain (losses) on cash flow hedge \| Foreign currency forward contracts
Reclassification Out of Accumulated Other Comprehensive Income [Line Items]
Net revenue	(2,568)	2,035
Cost of revenue	6	(13)
Research and development	99	(19)
Sales and marketing	230	(364)
General and administrative	$ 41	$ (59)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
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Amount before tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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The aggregate total amount of expenses directly related to the marketing or selling of products or services.

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