Property and Equipment, Net - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Total property and equipment	$ 6,592	$ 5,759
Less: Accumulated depreciation and amortization	(4,549)	(3,638)
Property and equipment, net	2,043	2,121
Laboratory Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	$ 4,305	3,872
Useful life (in years)	3 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment	$ 1,406	1,327
Useful life (in years)	Lesser of useful life or lease term
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Total property and equipment	$ 526	68
Useful life (in years)	3 years
Construction In Progress
Property Plant And Equipment [Line Items]
Total property and equipment	$ 94	300
Computer Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	$ 91	42
Useful life (in years)	3 years
Software
Property Plant And Equipment [Line Items]
Total property and equipment	$ 170	$ 150
Useful life (in years)	3 years

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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Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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