Segment Information and Enterprise Reporting - Analysis of Product Revenues Based upon Geographic Area Shipped (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014	Jan. 03, 2015
Revenue, Major Customer [Line Items]
Concentration Risk, Net Assets Amount, Geographic Area	$ 268,234		$ 268,234		$ 307,741
Concentration Risk, Net Assets Geographic Area, Percentage	100.00%		100.00%		100.00%
Analysis of Product Revenues Based upon the Geographic Area Shipped
Total product revenue	$ 144,603	$ 137,142	$ 439,572	$ 402,868
Total product revenue, in percentage	100.00%	100.00%	100.00%	100.00%
North and South America \| Reportable Geographical Components
Analysis of Product Revenues Based upon the Geographic Area Shipped
Total product revenue	$ 105,217	$ 99,563	$ 327,221	$ 287,678
Total product revenue, in percentage	72.80%	72.60%	74.40%	71.40%
Europe, Middle East and Africa \| Reportable Geographical Components
Analysis of Product Revenues Based upon the Geographic Area Shipped
Total product revenue	$ 25,729	$ 23,417	$ 74,125	$ 73,146
Total product revenue, in percentage	17.80%	17.10%	16.90%	18.20%
Asia and Australia \| Reportable Geographical Components
Analysis of Product Revenues Based upon the Geographic Area Shipped
Total product revenue	$ 13,657	$ 14,162	$ 38,226	$ 42,044
Total product revenue, in percentage	9.40%	10.30%	8.70%	10.40%
United States \| Reportable Geographical Components
Revenue, Major Customer [Line Items]
Concentration Risk, Net Assets Amount, Geographic Area	$ 118,795		$ 118,795		$ 144,541
Concentration Risk, Net Assets Geographic Area, Percentage	44.30%		44.30%		47.00%
Analysis of Product Revenues Based upon the Geographic Area Shipped
Total product revenue	$ 101,471	$ 95,289	$ 314,983	$ 274,924
International \| Reportable Geographical Components
Revenue, Major Customer [Line Items]
Concentration Risk, Net Assets Amount, Geographic Area	$ 149,439		$ 149,439		$ 163,200
Concentration Risk, Net Assets Geographic Area, Percentage	55.70%		55.70%		53.00%

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Carrying amount of total assets less total liabilities of a designated geographic area if disclosed as a concentration risk.

+ References

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-Publisher FASB

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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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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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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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