Consolidated Balance Sheets (Parenthetical) (USD $)	Aug. 31, 2011	Aug. 31, 2010
Consolidated Balance Sheets [Abstract]
Class A common stock, par value per share	$ 0.20	$ 0.20
Class A common stock, shares authorized	168,000,000	168,000,000
Class A common stock, shares issued	68,657,234	68,056,387
Class A common stock, shares outstanding	68,657,234	68,056,387

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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Total number of shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Shares outstanding equals shares issued minus shares held in treasury and other adjustments, if any.

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