Balance Sheet Components (Schedule of Property and Equipment, Net) (Details) - USD ($) $ in Thousands	Jul. 01, 2018	Dec. 31, 2017
Total property and equipment, gross	$ 129,060	$ 123,241
Accumulated depreciation and amortization	(99,923)	(102,581)
Total property and equipment, net	29,137	20,660
Computer equipment
Total property and equipment, gross	12,771	10,114
Furniture, fixtures and leasehold improvements
Total property and equipment, gross	21,269	21,640
Software
Total property and equipment, gross	33,051	28,997
Machinery and equipment
Total property and equipment, gross	$ 61,969	$ 62,490