Property, Plant & Equipment (Details) - USD ($)	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 [Abstract]
Depreciation	$ 2,075,000	$ 1,907,000	$ 4,101,000	$ 3,740,000
Property, plant and equipment	168,843,000		168,843,000		$ 164,145,000
Accumulated depreciation	(87,589,000)		(87,589,000)		(83,488,000)
Property, Plant and Equipment, Net	81,254,000		81,254,000		80,657,000
Capital expenditures in progress	6,900,000		6,900,000		5,014,000
Commitments for capital expenditures in progress	$ 1,149,000		$ 1,149,000		$ 3,461,000

Commitments For Capital Expenditures In Progress

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

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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.

+ References

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- References

No definition available.

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- Definition

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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- Definition

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.

+ References

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