Note 12 - Stock-based Compensation - Stock Option Activity (Details) - USD ($)	12 Months Ended
Aug. 31, 2022	Aug. 31, 2021
Number of shares, Outstanding (in shares)	1,426,651	1,127,968
Weighted average exercise price, Outstanding (in dollars per share)	$ 9.30	$ 9.63
Number of shares, Options granted (in shares)	174,840	419,874
Weighted average exercise price, Options granted (in dollars per share)	$ 16.97	$ 8.24
Number of shares, Options exercised (in shares)	(51,218)	(77,645)
Weighted average exercise price, Options exercised (in dollars per share)	$ 6.60	$ 8.18
Number of shares, Options terminated (in shares)	(5,546)	(43,546)
Weighted average exercise price, Options terminated (in dollars per share)	$ 18.23	$ 9.63
Number of shares, Outstanding (in shares)	1,544,727	1,426,651
Weighted average exercise price, Outstanding (in dollars per share)	$ 10.23	$ 9.30
Aggregate intrinsic value, Outstanding	$ 4,151,365
Number of shares, Exercisable (in shares)	1,156,211
Weighted average exercise price, Exercisable (in dollars per share)	$ 9.58
Aggregate intrinsic value, Exercisable	$ 3,394,957

Number of share options (or share units) exercised during the current period, including cashless exercises.

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- Definition

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.

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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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- Definition

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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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