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

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-Topic 718
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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 price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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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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Number of share options (or share units) exercised during the current period.

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Note 13 - Employee Stock Option and Retirement Plans - Summary of Stock Option Activity (Details) - $ / shares			3 Months Ended				6 Months Ended
	Jan. 15, 2019	Jan. 12, 2018	Feb. 28, 2019	Nov. 30, 2018	Feb. 28, 2018	Nov. 30, 2017	Feb. 28, 2019	Feb. 28, 2018
Balance (in shares)			3,457,000	3,143,000			3,143,000
Balance, weighted average price per share (in dollars per share)			$ 162.68	$ 153.05			$ 153.05
Granted, weighted average price per share (in dollars per share)			$ 207.84		$ 192.11		$ 221.74	$ 190.04
Exercised (in shares)			(207,000)	(117,000)
Exercised, weighted average price per share (in dollars per share)			$ 136.30	$ 132.81
Forfeited (in shares)			(61,000)	(24,000)
Forfeited, weighted average price per share (in dollars per share)			$ 152.19	$ 169.47
Balance (in shares)			3,216,000	3,457,000			3,216,000
Balance, weighted average price per share (in dollars per share)			$ 164.42	$ 162.68			$ 164.42
Non Performance Based [Member]
Granted (in shares)			6,115	454,598	15,363	553,942
Granted, weighted average price per share (in dollars per share)			$ 207.84	$ 221.93	$ 192.11	$ 189.98
LTIP [Member] \| Non Performance Based [Member]
Granted (in shares)			6,000	455,000
Granted, weighted average price per share (in dollars per share)			$ 207.84	$ 221.93
Director Plan [Member]
Granted (in shares)	20,576	18,963	21,000
Granted, weighted average price per share (in dollars per share)			$ 207.88