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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The amount of property, plant, and equipment recognized as of the acquisition date.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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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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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.

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Balance Sheet Components (PPE) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Nov. 07, 2019
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 16,123	$ 5,033
Less accumulated depreciation	(3,809)	(2,497)
Property and equipment, net	12,314	2,536
Depreciation expense	1,200	1,100	$ 900
Vesta Intermediate Funding, Inc
Property Plant And Equipment [Line Items]
Fixed assets acquired				$ 7,304
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,841	402
Leasehold improvements \| Vesta Intermediate Funding, Inc
Property Plant And Equipment [Line Items]
Fixed assets acquired				2,400
Manufacturing equipment and toolings
Property Plant And Equipment [Line Items]
Property and equipment, gross	8,175	1,928
Computer equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,250	682
Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,602	1,039
Office equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	111	156
Furniture and fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,144	$ 826
Manufacturing Equipment \| Vesta Intermediate Funding, Inc
Property Plant And Equipment [Line Items]
Fixed assets acquired				4,400
Capitalized Software \| Vesta Intermediate Funding, Inc
Property Plant And Equipment [Line Items]
Fixed assets acquired				$ 500