Composition of Certain Financial Statement Items - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property and Equipment
Property and equipment, gross	$ 1,601	$ 1,804
Less: accumulated depreciation and amortization	(799)	(810)
Property and equipment, net	802	994
Depreciation and amortization expenses	400	300	$ 100
Computer equipment and software
Property and Equipment
Property and equipment, gross	333	351
Furniture and office equipment
Property and Equipment
Property and equipment, gross	4	137
Manufacturing equipment
Property and Equipment
Property and equipment, gross	1,049	1,108
Research and development equipment
Property and Equipment
Property and equipment, gross	30	30
Leasehold improvements
Property and Equipment
Property and equipment, gross	$ 185	$ 178

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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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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+ 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.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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

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