Property, Plant and Equipment - Additional Information (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment
Depreciation and amortization expense	$ 1,217,000	$ 1,368,000
Depreciation	1,186,000	1,310,000
Amortization expense	31,000	58,000
Property, plant and equipment, Gross	33,694,000	32,473,000
Machinery and equipment
Property, Plant and Equipment
ROU assets	185,000	209,000
Property, plant and equipment, Gross	20,757,000	20,689,000
ATG
Property, Plant and Equipment
Construction in progress	1,087,000	$ 414,000
ATG \| Construction in progress (CIP) machinery & equipment and self-constructed assets
Property, Plant and Equipment
Property, plant and equipment, Gross	607,000
ATG \| Construction in progress (CIP) IT equipment and software
Property, Plant and Equipment
Property, plant and equipment, Gross	$ 480,000

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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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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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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Amount of lessee's right to use underlying asset under operating lease.

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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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