Property, Plant and Equipment - Summary of Impairment Charges (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jan. 25, 2015	Jan. 26, 2014
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	$ 6,326	$ 6,842
Machinery and equipment
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	6,281	6,215
Furniture and office equipment
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	43	86
Leasehold improvements
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	2	541
Cost of sales
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	2,810	4,341
Cost of sales | Machinery and equipment
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	2,799	4,019
Cost of sales | Furniture and office equipment
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	10	5
Cost of sales | Leasehold improvements
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	1	317
Product development and engineering
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	3,510	2,187
Product development and engineering | Machinery and equipment
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	3,477	2,173
Product development and engineering | Furniture and office equipment
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	33	12
Product development and engineering | Leasehold improvements
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	0	2
Selling, general and administrative expenses
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	6	314
Selling, general and administrative expenses | Machinery and equipment
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	5	23
Selling, general and administrative expenses | Furniture and office equipment
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	0	69
Selling, general and administrative expenses | Leasehold improvements
Impaired Long-Lived Assets Held and Used [Line Items]
Total impairment charge	$ 1	$ 222