Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 29, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 128,801	$ 128,790
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(107,825)	(106,469)
Property, Plant and Equipment, Net	20,976	22,321
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	74,956	75,094
Capitalized Software [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	32,861	32,696
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	14,953	14,951
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 6,031	$ 6,049

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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