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 amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Property and Equipment, Net
Total property and equipment	$ 8,666		$ 8,666		$ 8,519
Less: Accumulated depreciation	(8,105)		(8,105)		(7,785)
Total property and equipment, net	561		561		734
Depreciation expense	87	$ 292	360	$ 873
UK
Property and Equipment, Net
Total property and equipment, net	104		104		122
Furniture, fixtures and vehicles
Property and Equipment, Net
Total property and equipment	183		183		224
Computer hardware and software
Property and Equipment, Net
Total property and equipment	379		379		379
Leasehold improvements
Property and Equipment, Net
Total property and equipment	3,931		3,931		3,931
Lab equipment
Property and Equipment, Net
Total property and equipment	3,995		3,995		3,972
Construction in progress
Property and Equipment, Net
Total property and equipment	$ 178		$ 178		$ 13