Note 14 - Stock-based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions of Employee Stock Options (USD $)	3 Months Ended	6 Months Ended
Nov. 30, 2014	Feb. 28, 2015	Feb. 28, 2014	Feb. 28, 2015	Feb. 28, 2014
Note 14 - Stock-based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions of Employee Stock Options [Line Items]
Weighted average exercise price (in Dollars per share)	$ 131.31
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		0.06%	0.01%	0.06%	0.01%
Term structure of volatility		21.00%	23.00%	21.00%	23.00%
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		2.34%	2.48%	2.34%	2.61%
Term structure of volatility		31.00%	32.00%	31.00%	33.00%
Employee Stock Option [Member]
Note 14 - Stock-based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions of Employee Stock Options [Line Items]
Expected life (in years)		8 years 109 days	7 years 219 days	8 years 73 days	7 years 219 days
Dividend yield		1.29%	1.35%	1.35%	1.35%
Weighted average estimated fair value (in Dollars per share)		43.05	29.14	39.07	29.64
Weighted average exercise price (in Dollars per share)		147.05	106.03	135.40	106.69
Fair value as a percentage of exercise price		29.30%	27.50%	28.90%	27.80%

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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

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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

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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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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

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- Definition

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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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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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