Property and Equipment - Property and Equipment and Related Accumulated Depreciation (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Property and Equipment
Property and equipment, gross	$ 2,228	$ 2,228
Less accumulated depreciation	(2,219)	(2,164)
Property and equipment, net	9	64
Laboratory equipment
Property and Equipment
Property and equipment, gross	1,037	1,037
Software
Property and Equipment
Property and equipment, gross	92	92
Computer and office equipment
Property and Equipment
Property and equipment, gross	354	354
Leasehold improvements
Property and Equipment
Property and equipment, gross	$ 745	$ 745

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.

+ References

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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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