Note 14. Stock-Based Compensation (Detail) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options (Employee Stock Option [Member], USD $)	3 Months Ended
Nov. 30, 2012	Nov. 30, 2011
Dividend yield	1.30%	1.11%
Weighted average estimated fair value (in Dollars per share)	26.87	32.08
Weighted average exercise price (in Dollars per share)	92.22	94.84
Fair value as a percentage of exercise price	29.10%	33.80%
Minimum [Member]
Term structure of risk-free interest rate	0.16%	0.13%
Expected life (in years)	7 years 219 days	7 years 219 days
Term structure of volatility	24.00%	30.00%
Maximum [Member]
Term structure of risk-free interest rate	1.91%	2.41%
Expected life (in years)	7 years 292 days	7 years 292 days
Term structure of volatility	33.00%	36.00%

The discount rate from market value on purchase date that participants pay for shares.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Section 50

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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No definition available.

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