Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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- Definition

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 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.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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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.

+ References

No definition available.

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Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Property, Plant and Equipment, net
Property, plant and equipment, gross	$ 262,160		$ 262,160		$ 251,433
Accumulated depreciation and amortization	(166,718)		(166,718)		(157,538)
Property, plant and equipment, net	95,442		95,442		93,895
Depreciation expense	6,100	$ 6,100	12,200	$ 12,200
Land
Property, Plant and Equipment, net
Property, plant and equipment, gross	2,680		2,680		2,680
Buildings and improvements
Property, Plant and Equipment, net
Property, plant and equipment, gross	24,408		$ 24,408		24,338
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	16,791		$ 16,791		16,170
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	$ 218,281		$ 218,281		$ 208,245
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