Note 15 - Employee Stock Option and Retirement Plans - Stock Options Outstanding and Exercisable (Details) - $ / shares shares in Thousands	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015
Outstanding at fiscal year end (in shares)	3,143	3,366	3,364	3,117
Balance (in dollars per share)	$ 153.05	$ 139.29	$ 129.54	$ 100.71
Exercisable at fiscal year end (in shares)		918	970
Exercisable at fiscal year end (in dollars per share)		$ 105.14	$ 89.42

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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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-Name Accounting Standards Codification
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