Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Nov. 30, 2020	Aug. 31, 2020
Condensed Consolidated Balance Sheets [Abstract]
Allowance for doubtful accounts	$ 3,751	$ 4,159
Common stock, par value	$ 0.05	$ 0.05
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	27,056,000	27,056,000
Treasury stock, shares	13,028,000	13,175,000

Amount of allowance for credit loss on accounts receivable, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Face amount or stated value per share of common stock.

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

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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