Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment, Gross	$ 998	$ 984
Less accumulated depreciation	(592)	(330)
Net property and equipment	406	654
Leasehold Improvements [Member]
Property, Plant and Equipment, Gross	$ 432	432
Leasehold Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life	3 years
Leasehold Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life	2 years
Computer And Office Equipment [Member]
Property, Plant and Equipment, Useful Life	3 years
Property, Plant and Equipment, Gross	$ 60	63
Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life	7 years
Property, Plant and Equipment, Gross	$ 46	46
Scientific Equipment [Member]
Property, Plant and Equipment, Useful Life	7 years
Property, Plant and Equipment, Gross	$ 460	$ 443

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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- Definition

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

No definition available.

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