Deferred Revenue	9 Months Ended
Feb. 28, 2018
Revenue Recognition and Deferred Revenue [Abstract]
Deferred Revenue	Note 8. Deferred Revenue In February, 2018, a new customer entered into a contract with Greystone to purchase plastics pallets with shipments occurring from May, 2018 through about August, 2018. The customer prepaid $4,595,034 to provide funding to Greystone for procuring raw materials to produce the pallets. Revenue will be recognized by Greystone as pallets are shipped to the customer.

The entire disclosure for deferred revenues at the end of the reporting period, and description and amounts of significant changes that occurred during the reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 430
-URI http://asc.fasb.org/topic&trid=2122452

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