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Note 11 - Share-based Compensation - Other Information Related to Stock Options (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Feb. 28, 2021	Feb. 29, 2020
Expected volatility	47.30%	46.00%
Expected term of options (Year)	4 years	4 years
Expected dividend rate	0.00%	0.00%
Risk-free interest rate	0.30%	1.60%
Expected forfeiture rate	3.00%	3.10%
Weighted-average grant-date fair value (in dollars per share)	$ 3.66	$ 2.60
Intrinsic value of options exercised	$ 3,505	$ 4,879
Cash received from options exercised	$ 0	$ 0

X

- Definition

The estimated forfeiture rate over the option's term.

+ References

No definition available.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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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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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.

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

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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