Stock-Based Compensation - Allocation of Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 25, 2015	Oct. 26, 2014	Oct. 25, 2015	Oct. 26, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 5,117	$ 7,935	$ 13,397	$ 21,056
Inventories [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Net change in stock-based compensation capitalized into inventory	(233)	121	45	148
Cost of Sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	197	391	1,071	1,109
Selling, General and Administrative Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	2,933	4,620	6,006	12,132
Product Development And Engineering [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated Share-based Compensation Expense	$ 1,987	$ 2,924	$ 6,320	$ 7,815