Deferred Revenue	9 Months Ended
Feb. 28, 2019
Revenue Recognition and Deferred Revenue [Abstract]
Deferred Revenue	Note 8. Deferred Revenue Deferred revenue as of February 28, 2019 and May 31, 2018 represents advance payments from a customer to purchase plastic pallets with shipments expected to be complete by January 3, 2020. Greystone recognizes revenue as plastic pallets are shipped to the customer. Recognized revenue totaled $4,252,500 during the nine months ended February 28, 2019.

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

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