Note 14 - Stock-Based Compensation (Details) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options	12 Months Ended
Aug. 31, 2013	Aug. 31, 2012	Aug. 31, 2011
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	0.07%	0.06%	0.10%
Expected life (years)	3 months	3 months	3 months
Term structure of volatility	9.80%	14.80%	11.90%
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	0.16%	0.13%	0.18%
Expected life (years)	7 years 219 days	7 years 219 days	4 years
Term structure of volatility	24.00%	29.00%	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	1.91%	2.41%	1.88%
Expected life (years)	7 years 292 days	9 years 36 days	6 years 6 months
Term structure of volatility	33.00%	36.00%	35.00%

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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

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)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(i)

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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-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

-Subparagraph (f)(2)(ii)

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

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- Definition

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

-Subparagraph (f)(2)(iv)

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

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