Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, at cost	$ 54,548	$ 53,377
Less: accumulated depreciation and amortization	(18,395)	(16,375)
Property and equipment, net	36,153	37,002
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property and equipment, at cost	13,563	12,703
Manufacturing Equipment
Property Plant And Equipment [Line Items]
Property and equipment, at cost	7,815	7,754
Computers and Purchased Software
Property Plant And Equipment [Line Items]
Property and equipment, at cost	1,596	1,596
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, at cost	1,363	1,363
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, at cost	29,961	$ 29,961
Assets Not Yet in Service
Property Plant And Equipment [Line Items]
Property and equipment, at cost	$ 250