Segment Information and Enterprise Reporting (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 274,478	$ 225,167	$ 210,323
Concentration Risk, Long-lived Asset Geographic Area, Percentage	100.00%	100.00%	100.00%
Product	$ 741,324	$ 663,846	$ 599,334
Percentage Of Product Revenue Based On Geographic Area By Destination	100.00%	100.00%	100.00%
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Product	$ 506,815	$ 465,588	$ 421,628
Europe, Middle East and Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Product	$ 138,075	$ 112,273	$ 105,323
Percentage Of Product Revenue Based On Geographic Area By Destination	18.60%	16.90%	17.60%
Asia and Australia
Revenues from External Customers and Long-Lived Assets [Line Items]
Product	$ 72,449	$ 65,955	$ 55,675
Percentage Of Product Revenue Based On Geographic Area By Destination	9.80%	10.00%	9.30%
North and South America (excluding United States)
Revenues from External Customers and Long-Lived Assets [Line Items]
Product	$ 23,985	$ 20,030	$ 16,708
Percentage Of Product Revenue Based On Geographic Area By Destination	3.20%	3.00%	2.80%
Reportable Geographical Components [Member] \| United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration Risk, Percentage	68.40%	70.10%	70.30%
Reportable Geographical Components [Member] \| United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 263,860	$ 216,784	$ 203,553
Concentration Risk, Long-lived Asset Geographic Area, Percentage	96.10%	96.30%	96.80%
Reportable Geographical Components [Member] \| International
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-Lived Assets	$ 10,618	$ 8,383	$ 6,770
Concentration Risk, Long-lived Asset Geographic Area, Percentage	3.90%	3.70%	3.20%

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Total revenue from both the sale of goods during the reporting period as well as royalties earned during the period, excluding royalty revenue based on a third party settlement agreement, reduced by sales returns and allowances, and sales discounts.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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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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