Property, Plant and Equipment, Net - Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 68,630	$ 66,050
Less: Accumulated depreciation	(10,483)	(5,525)
Property, plant and equipment, net	58,147	60,525
Manufacturing equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	18,073	2,366
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	7,525	6,038
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment	1,648	1,815
Software, computer and other equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	7,772	2,702
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment	29,720	4,072
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 3,892	$ 49,057