Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details) - USD ($)	May 31, 2018	May 31, 2017
Property plant and equipment, gross	$ 41,941,336	$ 33,446,479
Less: Accumulated depreciation and amortization	(16,587,460)	(13,739,697)
Net Property, Plant and Equipment	25,353,876	19,706,782
Production Machinery and Equipment [Member]
Property plant and equipment, gross	35,270,326	27,493,614
Plant Buildings and Land [Member]
Property plant and equipment, gross	5,739,491	5,296,784
Leasehold Improvements [Member]
Property plant and equipment, gross	534,637	263,710
Furniture and Fixtures [Member]
Property plant and equipment, gross	$ 396,882	$ 392,371

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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