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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-Section 50
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-Topic 210
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The aggregate net amount of depreciation, amortization, and accretion recognized during an accounting period. As a noncash item, the net amount is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ 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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Supplemental Balance Sheet Information - Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,193		$ 2,166
Less: accumulated depreciation	(918)		(849)
Property and equipment, net	1,275		1,317
Depreciation and amortization	86	$ 38
Scientific equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,906		1,797
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	192		192
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	31		31
Computers and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	26		26
Construction in process
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 38		$ 120