Note 10. Common Stock and Earnings Per Share (Detail) - Weighted Average Shares Outstanding (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Nov. 30, 2011	Nov. 30, 2010
Basic EPS
Income available to common stockholders (in Dollars)	$ 45,544	$ 41,601
Income available to common stockholders	45,107	46,283
Income available to common stockholders (in Dollars per share)	$ 1.01	$ 0.90
Diluted EPS
Dilutive effect of stock options and restricted stock	996	1,204
Income available to common stockholders plus assumed conversions (in Dollars)	$ 45,544	$ 41,601
Income available to common stockholders plus assumed conversions	46,103	47,487
Income available to common stockholders plus assumed conversions (in Dollars per share)	$ 0.99	$ 0.88

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References+ Details

- Definition

The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References+ Details

- Definition

Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

+ References

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