Segment and Geographic Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from foreign external customers	$ 63,367	$ 70,682	$ 187,478	$ 213,941
Revenue from foreign external customers as percent of total	89.00%	86.00%	88.00%	86.00%
Total revenue	70,889	81,720	213,381	248,196
Total revenue as percentage	100.00%	100.00%	100.00%	100.00%
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from domestic external customers	7,522	11,038	25,903	34,255
Revenue from domestic external customers as percent of total	11.00%	14.00%	12.00%	14.00%
Asia Pacific (primarily China and Taiwan)
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from foreign external customers	40,488	40,431	117,202	128,210
Revenue from foreign external customers as percent of total	57.00%	50.00%	55.00%	52.00%
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from foreign external customers	12,424	16,656	37,736	52,977
Revenue from foreign external customers as percent of total	17.00%	20.00%	18.00%	21.00%
Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from foreign external customers	8,373	11,826	27,194	28,350
Revenue from foreign external customers as percent of total	12.00%	14.00%	13.00%	11.00%
Other Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue from foreign external customers	$ 2,082	$ 1,769	$ 5,346	$ 4,404
Revenue from foreign external customers as percent of total	3.00%	2.00%	2.00%	2.00%

Percent of Revenue By Geographical Area

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- Definition

Entity Wide Disclosure On Geographic Areas, Percent Of Revenue From External Customers Attributed To Foreign Countries

+ References

No definition available.

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- Definition

Entity Wide Revenue By Geographic Area, Percentage

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- Definition

Revenues from external customers attributed to the entity's country of domicile.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 280

-SubTopic 10

-Section 50

-Paragraph 41

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9038-108599

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 38

-Subparagraph a(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Revenues from external customers attributed to all foreign countries in total from which the entity derives revenues.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 280

-SubTopic 10

-Section 50

-Paragraph 41

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9038-108599

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 38

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ 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=6880815&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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