Related Party Transactions (Details Narrative) - USD ($)	12 Months Ended
May 31, 2019	May 31, 2018
Rent expense	$ 48,000	$ 48,000
Future minimum payments under capital lease 2020	1,966,428
Future minimum payments under capital lease 2021	1,966,428
Future minimum payments under capital lease 2022	1,865,328
TriEnda Holdings, L.L.C. [Member]
Purchases from related parties	42,349	68,302
Non-Cancelable Operating Lease [Member]
Future minimum payments under capital lease 2020	48,000
Future minimum payments under capital lease 2021	48,000
Future minimum payments under capital lease 2022	28,000
Yorktown's Grinding and Pelletizing Equipment [Member]
Payments of rental fees	27,500
Yorktown [Member]
Rent expense	1,430,000	1,430,000
Yorktown [Member] \| Oklahoma [Member]
Rent expense	4,000
Green Plastic Pallets [Member]
Revenue from service	225,600	$ 421,965
Account receivable	$ 38,760

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Cash payments to lessor's for use of assets under operating leases.

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