Note 14 - Stock-Based Compensation (Details) (USD $)	3 Months Ended
Nov. 30, 2013	Nov. 30, 2012
Note 14 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	72,203
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)	162,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 102.27
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in Shares)	194,000	333,000
Non-Performance Based [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)		635,308
Performance Based [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)		1,011,510
Performance Based [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized (in Dollars)	$ 61,400,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 years 292 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	36,695
Non-Performance Based [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	35,508
Performance and Non-Performance [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 109.49	$ 92.22
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 31.78	$ 26.87
Non-Employee Directors' Stock Option Plan [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance (in Shares)	250,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)	161,716
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 102.27
Employee Stock Purchase Plan [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Allocated Share-based Compensation Expense (in Dollars)	300,000	300,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 86.65	$ 78.53
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 16.64	$ 15.74
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in Shares)	16,363	18,102
Employee Stock Purchase Plan [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Allocated Share-based Compensation Expense (in Dollars)	$ 5,100,000	$ 5,200,000

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate number of common shares reserved for future issuance.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Gross number of share options (or share units) granted during the period.

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

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Number of shares issued during the period as a result of an employee stock purchase plan.

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