The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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

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No definition available.

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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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No definition available.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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

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Number of shares that have been repurchased and retired during the period.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Note 8 - Stockholders' Equity (Details Textual)							9 Months Ended
Note 8 - Stockholders' Equity (Details Textual)	Jun. 28, 2019	Jun. 03, 2019	Mar. 01, 2019 shares	Sep. 01, 2018 shares	Mar. 01, 2018 shares	Sep. 01, 2017 shares	May 31, 2019 $ / shares shares	May 31, 2018 $ / shares shares	Jan. 18, 2019 shares	Jan. 17, 2019 shares	Aug. 31, 2018 shares
Common Stock, Shares Authorized							15,000,000		15,000,000	10,000,000	15,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross							141,768	94,504
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period							0	8,820
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price \| $ / shares								$ 5.80
Stock Issued During Period, Shares, Employee Stock Purchase Plans			2,462	1,748	1,970	1,782
Stock Repurchased and Retired During Period, Shares							0	0
The 2019 Plan [member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized							800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross							0
The 2007 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross							141,768	94,504
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price \| $ / shares							$ 18.23	$ 9.18
Subsequent Event [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	2	2