Property, Plant and Equipment - Narrative (Details) (USD $)	12 Months Ended
Jan. 25, 2015	Jan. 26, 2014	Jan. 27, 2013
Property, Plant and Equipment [Line Items]
Net book value of equipment and machinery	$ 115,471,000us-gaap_PropertyPlantAndEquipmentNet	$ 110,121,000us-gaap_PropertyPlantAndEquipmentNet
Depreciation	21,100,000us-gaap_Depreciation	21,800,000us-gaap_Depreciation	17,900,000us-gaap_Depreciation
Machinery and equipment \| Foundry in China
Property, Plant and Equipment [Line Items]
Net book value of equipment and machinery	$ 7,600,000	$ 8,100,000

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 13

-Subparagraph a

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 7

Name:	us-gaap_PropertyPlantAndEquipmentNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant