The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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Note 15 - Stock-based Compensation - Summary of Stock Option Weighted Average Assumptions of Non-employee Director Stock Options (Details)			3 Months Ended		9 Months Ended
	Jan. 13, 2017	Jan. 15, 2016	May 31, 2017	May 31, 2016	May 31, 2017	May 31, 2016
Term structure of volatility
Dividend yield			1.18%	1.33%	1.18%	1.09%
Expected life (years) (Year)			7 years 146 days	7 years 182 days	7 years 146 days	7 years 255 days
Non Employee Directors Stock Option Plan [Member] \| Employee Stock Option [Member]
Term structure of volatility	22.70%	23.00%
Dividend yield	1.24%	1.05%
Term structure of risk-free interest rate	1.95%	1.62%
Expected life (years) (Year)	5 years 146 days	5 years 146 days