Property, Plant and Equipment (Details Narrative) - USD ($)	9 Months Ended
Feb. 28, 2019	Feb. 28, 2018
Production machinery and equipment, gross	$ 13,227,122
Production machinery includes deposits on equipment	1,390,839
Plant buildings and land net book value	2,925,517
Depreciation expense	$ 3,255,939	$ 2,476,050
Pallet Molds [Member]
Property plant and equipment useful life	3 years 6 months
Injection Molding Machines [Member]
Property plant and equipment useful life	12 years

Production machinery includes deposits on equipment.

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- Definition

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=84164758&loc=d3e45014-112735

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (e)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The cash outflow for acquisition of buildings (properties) whether for investment or use.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
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-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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