Property, Plant and Equipment, Net - Additional Information (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2017 USD ($) ft²	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Property, Plant and Equipment [Line Items]
Depreciation expense		$ 2,442	$ 1,410	$ 970
Area of interior floor space | ft²	30,000
Capital lease obligations		4,500	5,700
Foreign currency transaction gain (loss) unrealized		200	(600)
Property, Plant and Equipment
Property, Plant and Equipment [Line Items]
Amount of property, plant and equipment and build-out facility	$ 4,200	24,800
Other Current Liabilities
Property, Plant and Equipment [Line Items]
Capital lease obligations		$ 200	$ 300