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.

+ References

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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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Balance Sheet Components - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 3,788	$ 1,729
Less: Accumulated depreciation and amortization		(946)	(1,303)
Property and equipment, net	$ 2,846	2,880	486
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross		517	76
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross		1,217	1,059
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross		76	405
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross		1,978	189
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 38	$ 60