Commitments	12 Months Ended
May 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments	Note 15. COMMITMENTS At May 31, 2018, Greystone had outstanding commitments totaling $2,071,400 for the acquisition of equipment.

The entire disclosure for significant arrangements with third parties, which includes operating lease arrangements and arrangements in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services, and operating lease arrangements. Descriptions may include identification of the specific goods and services, period of time covered, minimum quantities and amounts, and cancellation rights.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-URI http://asc.fasb.org/topic&trid=2144648

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