Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Feb. 28, 2019	Aug. 31, 2018
Condensed Consolidated Balance Sheets [Abstract]
Allowance for doubtful accounts	$ 4,185	$ 3,555
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	13,109,000	13,159,000

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 210
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-Section S99
-Paragraph 1
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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