Segment Information and Operations By Geographic Area (Schedule Of Net Revenue By Geography Periods) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 02, 2016	Sep. 27, 2015	Oct. 02, 2016	Sep. 27, 2015
Segment Reporting Information [Line Items]
Total net revenues	$ 338,458	$ 341,893	$ 960,369	$ 939,832
United States [Member]
Segment Reporting Information [Line Items]
Total net revenues	217,631	213,913	610,505	552,787
Americas Excluding United States [Member]
Segment Reporting Information [Line Items]
Total net revenues	7,604	5,823	19,488	13,194
EMEA [Member]
Segment Reporting Information [Line Items]
Total net revenues	60,034	77,725	176,192	234,827
Asia Pacific [Member]
Segment Reporting Information [Line Items]
Total net revenues	$ 53,189	$ 44,432	$ 154,184	$ 139,024