Property, Plant and Equipment (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Property, Plant and Equipment
Gross property, plant, and equipment	$ 186,523,000		$ 186,523,000		$ 162,061,000
Less accumulated depreciation and amortization, including accumulated amortization of finance leases	(102,566,000)		(102,566,000)		(103,839,000)
Property, plant, and equipment - net	83,957,000		83,957,000		58,222,000
Depreciation	2,269,000	$ 2,041,000	6,083,000	$ 6,049,000
Impairments of property, plant, and equipment			0	$ 0
Land
Property, Plant and Equipment
Gross property, plant, and equipment	5,256,000		5,256,000		6,224,000
Improvements to land and leaseholds
Property, Plant and Equipment
Gross property, plant, and equipment	20,762,000		20,762,000		15,416,000
Buildings
Property, Plant and Equipment
Gross property, plant, and equipment	34,468,000		34,468,000		27,206,000
Machinery and equipment, including equipment under finance leases
Property, Plant and Equipment
Gross property, plant, and equipment	122,935,000		122,935,000		112,021,000
Construction in progress
Property, Plant and Equipment
Gross property, plant, and equipment	$ 3,102,000		$ 3,102,000		$ 1,194,000