Balance Sheet Components (Schedule of Property and Equipment, Net) (Details) - USD ($) $ in Thousands	Jul. 01, 2018	Dec. 31, 2017
Total property and equipment, gross	$ 16,835	$ 7,270
Accumulated depreciation and amortization	(4,446)	(3,387)
Total property and equipment, net	12,389	3,883
Machinery and Equipment [Member]
Total property and equipment, gross	8,290	6,067
Computer Equipment [Member]
Total property and equipment, gross	4,798	50
Software
Total property and equipment, gross	2,791	180
Leasehold Improvements
Total property and equipment, gross	548	530
Furniture and fixtures
Total property and equipment, gross	$ 408	$ 443