Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details) - USD ($)	Aug. 31, 2018	May 31, 2018
Property plant and equipment, gross	$ 45,489,086	$ 41,941,336
Less: Accumulated depreciation and amortization	(17,640,463)	(16,587,460)
Net Property, Plant and Equipment	27,848,623	25,353,876
Production Machinery and Equipment [Member]
Property plant and equipment, gross	38,462,159	35,270,326
Plant Buildings and Land [Member]
Property plant and equipment, gross	5,855,140	5,739,491
Leasehold Improvements [Member]
Property plant and equipment, gross	735,601	534,637
Furniture and Fixtures [Member]
Property plant and equipment, gross	$ 436,186	$ 396,882

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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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.

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