Balance Sheet Details - Property and Equipment, net (Details) - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 31, 2017
Summary of property and equipment, net
Property and equipment, gross	$ 91,918	$ 80,870
Accumulated depreciation and amortization	(70,666)	(65,189)
Property and equipment, net	21,252	15,681
Test equipment
Summary of property and equipment, net
Property and equipment, gross	44,040	39,952
Computer equipment and software
Summary of property and equipment, net
Property and equipment, gross	39,833	32,175
Furniture and fixtures
Summary of property and equipment, net
Property and equipment, gross	2,869	2,714
Leasehold improvements
Summary of property and equipment, net
Property and equipment, gross	$ 5,176	$ 6,029

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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