Segment Information (Schedule of Net Revenue by Geographic Areas) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017
Segment Reporting Information [Line Items]
Total net revenue	$ 400,586	$ 355,483	$ 1,112,379	$ 1,009,863
United States (U.S.)
Segment Reporting Information [Line Items]
Total net revenue	280,639	235,584	762,619	663,096
Americas (excluding U.S.)
Segment Reporting Information [Line Items]
Total net revenue	8,145	8,804	19,611	19,870
EMEA
Segment Reporting Information [Line Items]
Total net revenue	64,917	62,161	200,227	175,810
Asia Pacific
Segment Reporting Information [Line Items]
Total net revenue	$ 46,885	$ 48,934	$ 129,922	$ 151,087