Employee Benefit Plans (Schedule Of Total Stock-Based Compensation Expense Resulting From Stock Options, Restricted Stock Awards, And The Employee Stock Purchase Plan) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2017	Jul. 03, 2016	Jul. 02, 2017	Jul. 03, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 5,701	$ 5,019	$ 10,829	$ 9,430
Cost Of Revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	542	451	978	890
Research And Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,373	1,118	2,692	1,984
Sales And Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,438	1,338	2,685	2,535
General And Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 2,348	$ 2,112	$ 4,474	$ 4,021