SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	6 Months Ended
	Oct. 31, 2020
Office furniture and equipment [Member]
Property plant and equipment estimated useful life	10 years
Computer equipment and software [Member]
Property plant and equipment estimated useful life	5 years
Refinery land improvements [Member]
Property plant and equipment estimated useful life	15 years
Refinery land easements [Member]
Property plant and equipment estimated useful life	10 years