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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

+ References

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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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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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Composition of Certain Financial Statement Items - Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Property and Equipment
Property and equipment, gross	$ 1,846		$ 1,846		$ 1,804
Less: accumulated depreciation	(981)		(981)		(810)
Property and equipment, net	865		865		994
Depreciation and amortization expenses	98	$ 56	188	$ 99
Computer equipment and software
Property and Equipment
Property and equipment, gross	333		333		351
Furniture and office equipment
Property and Equipment
Property and equipment, gross	148		148		137
Manufacturing equipment
Property and Equipment
Property and equipment, gross	1,150		1,150		1,108
Research and development equipment
Property and Equipment
Property and equipment, gross	30		30		30
Leasehold improvements
Property and Equipment
Property and equipment, gross	$ 185		$ 185		$ 178