14. STOCK-BASED COMPENSATION (Details 2) - Stock Option and RSU Transactions	3 Months Ended
Aug. 31, 2020 shares
Available shares, beginning (in thousands)	1,650
Options granted (in thousands)	(200)
RSUs granted (in thousands)	(196)
Options cancelled (in thousands)	188
RSUs cancelled (in thousands)	2
Options expired (in thousands)	(125)
Available shares, ending (in thousands)	1,319

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of shares related to Restricted Stock Award forfeited during the period.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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