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Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 448	$ 417
Less: Accumulated depreciation and amortization	(177)	(176)
Property and Equipment, Net	271	241
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	299	299
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	53	53
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	19	56
Software [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	9	$ 9
Lab Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Gross	$ 67

X

- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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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.

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