Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Details) - USD ($)	Aug. 31, 2019	May 31, 2019
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 54,932,474	$ 53,706,523
Less: Accumulated depreciation and amortization	(22,330,019)	(21,026,051)
Net Property, Plant and Equipment	32,602,455	32,680,472
Production Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	46,527,139	45,645,910
Plant Buildings and Land [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	6,403,855	6,336,855
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	1,174,340	979,890
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	591,074	563,074
Right-to-use Assets Under Operating Leases [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 236,066	$ 180,794