Balance Sheet Components (Schedule of Intangibles, Net) (Details) - USD ($) $ in Thousands	Apr. 01, 2018	Dec. 31, 2017
Intangible Assets [Line Items]
Gross	$ 134,144	$ 134,144
Accumulated Amortization	(111,695)	(109,156)
Net	22,449	24,988
Technology
Intangible Assets [Line Items]
Gross	66,599	66,599
Accumulated Amortization	(62,724)	(62,172)
Net	3,875	4,427
Customer contracts and relationships
Intangible Assets [Line Items]
Gross	56,500	56,500
Accumulated Amortization	(39,186)	(37,430)
Net	17,314	19,070
Other
Intangible Assets [Line Items]
Gross	11,045	11,045
Accumulated Amortization	(9,785)	(9,554)
Net	$ 1,260	$ 1,491