Revenue Recognition (Income Statement Impact) (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 01, 2018	Apr. 02, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenue	$ 344,973	$ 323,657
Cost of revenue	240,468	226,725
Gross profit	104,505	96,932
Provision for income taxes	2,393	7,535
Net income	5,590	$ 15,994
Adjustments \| Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenue	2,273
Cost of revenue	203
Gross profit	2,070
Provision for income taxes	357
Net income	1,713
Balance without adoption of ASC 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net revenue	347,246
Cost of revenue	240,671
Gross profit	106,575
Provision for income taxes	2,750
Net income	$ 7,303

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.

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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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