Income Taxes	9 Months Ended
Feb. 28, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Note 12. Income Taxes On December 22, 2017, the President signed into legislation The Tax Cuts and Jobs Act (the Act). The Act changes existing U.S. tax law and includes numerous provisions that will affect Greystone’s business, including income tax accounting, disclosure and tax compliance. As a result of the changes in tax rates as provided in the Act and reassessing deferred income taxes using state income tax rates, Greystone revalued all deferred tax assets and liabilities, and as a result, the deferred taxes at February 28, 2018 decreased $474,100 and the provision for income taxes for the three months ended February 28, 2018 increased by a like amount.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

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