Note 14. Stock-Based Compensation (Detail) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options (USD $)	3 Months Ended
Nov. 30, 2011	Nov. 30, 2010
Term structure of risk-free interest rate	0.13% - 2.41%	0.18% - 1.88%
Expected life	7.56 - 7.75 years	5.75 - 6.51 years
Term structure of volatility	30% - 36%	26% - 34%
Dividend yield	1.11%	1.25%
Weighted average estimated fair value (in Dollars per share)	$ 32.08	$ 24.42

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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