Property and Equipment - Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 8,818	$ 6,107
Less: accumulated depreciation and amortization	(3,412)	(3,060)
Property and equipment, net	5,406	3,047
Research and development equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,176	1,086
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,621	1,418
Tools and molds
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,305	1,303
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,506	1,500
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,152	624
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 58	$ 176

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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