Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 4,888	$ 2,919
Less: accumulated depreciation	(931)	(355)
Property and equipment, net	3,957	2,564
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	848	307
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	370	89
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,678	2,495
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	609	28
Construction in process
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 383	$ 0

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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