PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	$ 302,824	$ 285,687
Less: accumulated depreciation	108,743	95,894
Property, plant and equipment, net	194,081	189,793
Land [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	7,915	7,262
Building [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	67,211	63,224
Equipment [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	210,608	201,341
Construction in Progress [Member]
Property, plant and equipment [Abstract]
Property, plant and equipment, gross	$ 17,090	$ 13,860

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

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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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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