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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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Property, Plant and Equipment, net
Property, plant and equipment, gross	$ 303,775		$ 296,668
Accumulated depreciation and amortization	(224,959)		(219,107)
Property, plant and equipment, net	78,816		77,561
Depreciation and amortization expense	6,300	$ 6,600
Land
Property, Plant and Equipment, net
Property, plant and equipment, gross	2,447		2,529
Buildings and improvements
Property, Plant and Equipment, net
Property, plant and equipment, gross	$ 25,457		24,800
Buildings and improvements \| Minimum
Property, Plant and Equipment, net
Useful Life (Years)	30 years
Buildings and improvements \| Maximum
Property, Plant and Equipment, net
Useful Life (Years)	40 years
Office furniture and equipment
Property, Plant and Equipment, net
Property, plant and equipment, gross	$ 18,644		18,057
Office furniture and equipment \| Minimum
Property, Plant and Equipment, net
Useful Life (Years)	5 years
Office furniture and equipment \| Maximum
Property, Plant and Equipment, net
Useful Life (Years)	8 years
Machinery and equipment
Property, Plant and Equipment, net
Property, plant and equipment, gross	$ 257,227		$ 251,282
Machinery and equipment \| Minimum
Property, Plant and Equipment, net
Useful Life (Years)	5 years
Machinery and equipment \| Maximum
Property, Plant and Equipment, net
Useful Life (Years)	7 years