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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The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Supplemental Balance Sheet Information - Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 5,903		$ 5,863
Less: accumulated depreciation	(1,811)		(1,740)
Property and equipment, net	4,092		4,123
Depreciation and amortization	263	$ 148
Scientific equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,760		5,476
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	0		192
Computers and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	52		46
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	30		30
Construction in process
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 61		$ 119