Segment Information and Enterprise Reporting - Analysis of Product Revenues Based upon Geographic Area Shipped (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 04, 2015	Jun. 28, 2014	Jul. 04, 2015	Jun. 28, 2014	Jan. 03, 2015
Revenue, Major Customer [Line Items]
Concentration Risk, Net Assets Amount, Geographic Area	$ 284,450		$ 284,450		$ 307,738
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	$ 147,612	$ 133,493	$ 294,969	$ 265,725
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	$ 110,526	$ 95,462	$ 222,004	$ 188,115
Total product revenue, in percentage	74.90%	71.50%	75.30%	70.80%
Europe, Middle East and Africa \| Reportable Geographical Components
Analysis of Product Revenues Based upon the Geographic Area Shipped
Total product revenue	$ 24,335	$ 22,717	$ 48,396	$ 49,729
Total product revenue, in percentage	16.50%	17.00%	16.40%	18.70%
Asia and Australia \| Reportable Geographical Components
Analysis of Product Revenues Based upon the Geographic Area Shipped
Total product revenue	$ 12,751	$ 15,314	$ 24,569	$ 27,881
Total product revenue, in percentage	8.60%	11.50%	8.30%	10.50%
United States \| Reportable Geographical Components
Revenue, Major Customer [Line Items]
Concentration Risk, Net Assets Amount, Geographic Area	$ 124,886		$ 124,886		$ 144,541
Concentration Risk, Net Assets Geographic Area, Percentage	43.90%		43.90%		47.00%
Analysis of Product Revenues Based upon the Geographic Area Shipped
Total product revenue	$ 106,236	$ 91,589	$ 213,512	$ 179,636
Non-US [Member] \| Reportable Geographical Components
Revenue, Major Customer [Line Items]
Concentration Risk, Net Assets Amount, Geographic Area	$ 159,564		$ 159,564		$ 163,197
Concentration Risk, Net Assets Geographic Area, Percentage	56.10%		56.10%		53.00%

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- Definition

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

-Name Accounting Standards Codification

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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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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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