Note 7 - Accounting for Share-based Compensation - Stock Option Activity (Details) - $ / shares	3 Months Ended
Feb. 29, 2020	Nov. 30, 2019
Outstanding Options (in shares)	5,060,310
Outstanding Options, weighted-average exercise price (in dollars per share)	$ 46.36	$ 46.04
Granted (in shares)	1,021,629
Granted, weighted-average exercise price (in dollars per share)	$ 48.21
Exercised (in shares)	(25,594)
Exercised, weighted-average exercise price (in dollars per share)	$ 35.44
Forfeited or cancelled (in shares)	(73,601)
Forfeited or cancelled, weighted-average exercise price (in dollars per share)	$ 53.71
Outstanding Options (in shares)	5,982,744

For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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