Selected Balance Sheet Information - Schedule of property, plant and equipment, net (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Property and equipment, net
Property and equipment, Gross	$ 1,302	$ 1,302
Less accumulated depreciation and amortization	(877)	(695)
Total	425	607
Computers and office equipment [Member]
Property and equipment, net
Property and equipment, Gross	852	852
Leasehold Improvements [Member]
Property and equipment, net
Property and equipment, Gross	439	439
Software [Member]
Property and equipment, net
Property and equipment, Gross	$ 11	$ 11

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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