Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	May 31, 2012	Aug. 31, 2011
Allowance for doubtful accounts	$ 8,560	$ 9,475
Investment grants	$ 606	$ 815
Common stock, par value	$ 1.00	$ 1.00
Common stock, shares authorized	75,000	75,000
Common stock, shares issued	47,948	47,816
Treasury stock, shares	18,408	17,207

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No definition available.

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- Definition

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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- Definition

Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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- Definition

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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- Definition

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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