Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Feb. 28, 2013	Aug. 31, 2012
Allowance for doubtful accounts	$ 10,505	$ 9,190
Investment grants	$ 515	$ 579
Common stock, par value	$ 1.00	$ 1.00
Common stock, shares authorized	75,000	75,000
Common stock, shares issued	48,083	47,958
Treasury stock, shares	18,661	18,649

Government subsidies for plan expansion, net of accumulated amortization.

No definition available.

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

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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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