Property and Equipment, Net - (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Property and Equipment, Net
Property and equipment, gross	$ 17,236	$ 13,876
Less: accumulated depreciation and amortization	(5,146)	(2,469)
Property and equipment, net	12,090	11,407
Depreciation and amortization expense	2,688	1,677
Research equipment
Property and Equipment, Net
Property and equipment, gross	10,703	7,787
Leasehold improvements
Property and Equipment, Net
Property and equipment, gross	5,368	4,825
Computer equipment
Property and Equipment, Net
Property and equipment, gross	463	167
Furniture and fixtures
Property and Equipment, Net
Property and equipment, gross	93	70
Construction in progress
Property and Equipment, Net
Property and equipment, gross	$ 609	$ 1,027

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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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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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.

+ References

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