Segment Information Net Sales Activity by Segment (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Oct. 26, 2014	Oct. 27, 2013	Oct. 26, 2014	Oct. 27, 2013
Revenue from External Customer [Line Items]
Net sales	$ 148,890	$ 141,026	$ 427,491	$ 468,443
Semiconductor Products Group [Member]
Revenue from External Customer [Line Items]
Net sales	148,435	137,389	425,630	454,097
All others [Member]
Revenue from External Customer [Line Items]
Net sales	$ 455	$ 3,637	$ 1,861	$ 14,346

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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=26872669&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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration