Property, Plant and Equipment (Details) - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Property, Plant and Equipment
Gross property, plant, and equipment	$ 162,729,000		$ 162,061,000
Less accumulated depreciation and amortization, including accumulated amortization of finance leases	(105,150,000)		(103,839,000)
Property, plant, and equipment - net	57,579,000		58,222,000
Depreciation	1,938,000	$ 1,990,000
Impairments of property, plant, and equipment	0	$ 0
Land
Property, Plant and Equipment
Gross property, plant, and equipment	6,215,000		6,224,000
Improvements to land and leaseholds
Property, Plant and Equipment
Gross property, plant, and equipment	15,412,000		15,416,000
Buildings
Property, Plant and Equipment
Gross property, plant, and equipment	27,080,000		27,206,000
Machinery and equipment, including equipment under finance leases
Property, Plant and Equipment
Gross property, plant, and equipment	112,315,000		112,021,000
Construction in progress
Property, Plant and Equipment
Gross property, plant, and equipment	$ 1,707,000		$ 1,194,000

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 of accumulated depreciation and amortization from plant, property, and equipment and right-of-use asset from finance lease.

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Amount, after accumulated depreciation and amortization, of property, plant, and equipment and finance lease right-of-use asset.

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Amount, before accumulated depreciation and amortization, of property, plant, and equipment and finance lease right-of-use asset.

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