Segment and Geographic Information (Schedule of Revenue by Major Geographic Area) (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017 USD ($)	Oct. 01, 2016 USD ($)	Sep. 30, 2017 USD ($) segment	Oct. 01, 2016 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of operating segments \| segment			1
Proceeds from sale of assets and business units, net of cash sold			$ 967	$ 1,972
Gain on sale of business unit			(1,496)	2,646
Total revenue	$ 91,971	$ 113,225	$ 290,695	$ 308,946
Total revenue as percentage	100.00%	100.00%	100.00%	100.00%
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 68,677	$ 83,797	$ 207,081	$ 216,964
Total revenue as percentage	75.00%	74.00%	71.00%	70.00%
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 10,972	$ 13,111	$ 32,631	$ 43,849
Total revenue as percentage	12.00%	12.00%	11.00%	14.00%
Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 12,322	$ 16,317	$ 50,983	$ 48,133
Total revenue as percentage	13.00%	14.00%	18.00%	16.00%

Entity Wide Revenue By Geographic Area, Percentage

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- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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- Definition

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).

+ References

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 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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