The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Paragraph 22
-Subparagraph (e)
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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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Property, Plant and Equipment - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 356,000	$ 339,000	$ 1,072,000	$ 902,000
Amortization expense	15,000	$ 18,000	50,000	$ 59,000
Construction in progress	222,000		222,000		$ 331,000
Property, plant and equipment, Gross	32,690,000		32,690,000		$ 32,050,000
Construction in progress (CIP) machinery & equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	192,000		192,000
Construction in progress (CIP) building improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	22,000		22,000
Construction in progress (CIP) IT equipment and software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, Gross	$ 8,000		$ 8,000