Equipment - Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Equipment, gross	$ 11,773	$ 11,309
Accumulated depreciation	(8,891)	(8,307)
Equipment, net	2,882	3,002
Laboratory equipment
Property, Plant and Equipment [Line Items]
Equipment, gross	8,008	7,444
Office equipment and leasehold improvements
Property, Plant and Equipment [Line Items]
Equipment, gross	3,191	3,043
Process development equipment not yet in service
Property, Plant and Equipment [Line Items]
Equipment, gross	$ 574	$ 822

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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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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