Property, Plant and Equipment (Details) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment
Gross property, plant, and equipment	$ 178,925,000	$ 176,612,000
Less: accumulated depreciation and amortization, including accumulated amortization of finance leases	(103,551,000)	(101,033,000)
Property, plant, and equipment - net	75,374,000	75,579,000
Depreciation	9,452,000	9,949,000
Impairments of property, plant, and equipment	0	0
Land
Property, Plant and Equipment
Gross property, plant, and equipment	5,864,000	5,869,000
Improvements to land and leaseholds
Property, Plant and Equipment
Gross property, plant, and equipment	19,566,000	19,404,000
Buildings
Property, Plant and Equipment
Gross property, plant, and equipment	31,703,000	31,447,000
Machinery and equipment, including equipment under finance leases
Property, Plant and Equipment
Gross property, plant, and equipment	117,377,000	118,190,000
Construction in progress
Property, Plant and Equipment
Gross property, plant, and equipment	$ 4,415,000	$ 1,702,000

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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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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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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