Note 14 - Stock-Based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options (USD $)	3 Months Ended
Nov. 30, 2013	Nov. 30, 2012
Note 14 - Stock-Based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options [Line Items]
Term structure of risk-free interest rate	0.04%	0.10%
Expected life (in years)	3 months	3 months
Term structure of volatility	8.66%	10.00%
Dividend yield	1.37%	1.32%
Employee Stock Option [Member]
Note 14 - Stock-Based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options [Line Items]
Dividend yield	1.35%	1.30%
Weighted average estimated fair value (in Dollars per share)	$ 31.78	$ 26.87
Weighted average exercise price (in Dollars per share)	$ 109.49	$ 92.22
Fair value as a percentage of exercise price	29.00%	29.10%
Employee Stock Option [Member] \| Minimum [Member]
Note 14 - Stock-Based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options [Line Items]
Term structure of risk-free interest rate	0.08%	0.16%
Expected life (in years)	7 years 219 days	7 years 219 days
Term structure of volatility	23.00%	24.00%
Employee Stock Option [Member] \| Maximum [Member]
Note 14 - Stock-Based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options [Line Items]
Term structure of risk-free interest rate	2.61%	1.91%
Expected life (in years)	7 years 292 days	7 years 292 days
Term structure of volatility	33.00%	33.00%

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Discount rate from fair value on purchase date that participants pay for shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(iii)

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

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- Definition

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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