Related Party Transactions/Activity (Details Narrative) - USD ($)	9 Months Ended
Feb. 28, 2018	Feb. 28, 2017
Green Plastic Pallets [Member]
Sales	$ 330,144	$ 220,325
Account receivable	55,080
Yorktown Management & Financial Services, LLC [Member]
Payments of rental fees	1,072,500	1,100,000
Operating lease rental fees	4,000
TriEnda Holdings, LLC [Member]
Sales	0	519,814
Scrap material purchase amount	123,072	$ 24,265
Yorktown's Grinding Equipment [Member]
Payments of rental fees	22,500
Yorktown's Pelletizing Equipment [Member]
Payments of rental fees	$ 5,000

For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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