Property and Equipment - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Total cost	$ 26,923	$ 25,787
Less: Accumulated depreciation	(19,223)	(17,473)
Property and equipment, net	7,700	8,314
Equipment and Tooling
Property Plant And Equipment [Line Items]
Total cost	$ 22,896	22,150
Equipment and Tooling \| Minimum
Property Plant And Equipment [Line Items]
Useful Life	3 years
Equipment and Tooling \| Maximum
Property Plant And Equipment [Line Items]
Useful Life	5 years
Computer Equipment
Property Plant And Equipment [Line Items]
Total cost	$ 3,007	2,888
Computer Equipment \| Minimum
Property Plant And Equipment [Line Items]
Useful Life	3 years
Computer Equipment \| Maximum
Property Plant And Equipment [Line Items]
Useful Life	5 years
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Useful Life	10 years
Total cost	$ 738	$ 749
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total cost	$ 282
Leasehold Improvements \| Minimum
Property Plant And Equipment [Line Items]
Useful Life	2 years
Leasehold Improvements \| Maximum
Property Plant And Equipment [Line Items]
Useful Life	3 years

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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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