Subsequent Event	3 Months Ended
Aug. 31, 2016
Subsequent Events [Abstract]
Subsequent Event	Note 11. Subsequent Event Effective September 1, 2016, Greystone’s board of directors authorized the issuance of warrants to purchase 250,000 shares of Greystone’s common stock for $0.01 per share to each of Warren F. Kruger, President and CEO, and Robert B. Rosene, Jr., a member of Greystone’s board, as compensation for providing guarantees on Greystone’s debt with International Bank of Commerce. The warrants have a vesting period of two years and expire August 31, 2026. The issuance will be capitalized as debt issue cost as of the measurement date for approximately $125,000 and amortized over the remaining guaranty term.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

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