Note 14 - Stock-Based Compensation (Details) (USD $)	0 Months Ended			1 Months Ended		3 Months Ended				12 Months Ended				3 Months Ended					12 Months Ended		3 Months Ended										0 Months Ended				1 Months Ended	12 Months Ended		1 Months Ended	0 Months Ended	1 Months Ended	12 Months Ended			3 Months Ended		0 Months Ended	12 Months Ended
	Jan. 15, 2013	Jan. 13, 2012	Jan. 14, 2011	Apr. 30, 2013	Jul. 31, 2012	Aug. 31, 2013	May 31, 2013	May 31, 2012	Feb. 29, 2012	Aug. 31, 2013	Aug. 31, 2012	Aug. 31, 2011	Dec. 16, 2008	Nov. 30, 2012 Performance Based [Member]	Aug. 31, 2012 Performance Based [Member]	Aug. 31, 2011 Performance Based [Member]	Feb. 28, 2011 Performance Based [Member]	Nov. 30, 2010 Performance Based [Member]	Aug. 31, 2013 Performance Based [Member]	Aug. 31, 2011 Performance Based [Member]	Feb. 28, 2013 Non-Performance Based [Member]	Nov. 30, 2012 Non-Performance Based [Member]	Aug. 31, 2012 Non-Performance Based [Member]	May 31, 2011 Non-Performance Based [Member]	Nov. 30, 2010 Non-Performance Based [Member]	Nov. 30, 2012 Performance and Non-Performance [Member]	Aug. 31, 2012 Performance and Non-Performance [Member]	Nov. 30, 2011 Performance and Non-Performance [Member]	Nov. 30, 2010 Performance and Non-Performance [Member]	Aug. 31, 2013 Non-Employee Directors' Stock Option Plan [Member]	Apr. 08, 2013 Restricted Stock [Member]	Apr. 14, 2011 Restricted Stock [Member]	Nov. 08, 2010 Restricted Stock [Member]	Feb. 09, 2010 Restricted Stock [Member]	Jan. 27, 2011 Restricted Stock [Member]	Aug. 31, 2013 Restricted Stock [Member]	Aug. 31, 2012 Restricted Stock [Member]	Jul. 22, 2011 Restricted Stock Units (RSUs) [Member]	Nov. 08, 2010 Restricted Stock Units (RSUs) [Member]	Jan. 27, 2011 Restricted Stock Units (RSUs) [Member]	Aug. 31, 2013 Employee Stock Purchase Plan [Member]	Aug. 31, 2012 Employee Stock Purchase Plan [Member]	Aug. 31, 2011 Employee Stock Purchase Plan [Member]	Nov. 30, 2011 Non-Performance Based [Member]	Nov. 30, 2011 Performance Based [Member]	Jan. 13, 2012 Director [Member]	Aug. 31, 2013 Employee Stock Purchase Plan [Member]	Aug. 31, 2012 Employee Stock Purchase Plan [Member]	Aug. 31, 2011 Employee Stock Purchase Plan [Member]
Note 14 - Stock-Based Compensation (Details) [Line Items]
Allocated Share-based Compensation Expense (in Dollars)																			$ 18,300,000	$ 7,900,000																					$ 1,200,000	$ 1,300,000	$ 1,100,000				$ 40,000,000	$ 22,000,000	$ 25,800,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized (in Dollars)						10,400,000				10,400,000	39,200,000								50,300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition										4 years 219 days	3 years 36 days								3 years 6 months
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount (in Dollars)										$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	18,781	20,976	14,514		241,546	0	0	0	0	1,674,966	1,468,513	998,038		1,011,510	241,546	17,842	65,224	809,239			9,367	635,308	120,847	6,408	84,811																			419,593	665,551	5,244
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in Dollars per share)																$ 96.10	$ 99.78				$ 92.55			$ 103.30		$ 92.22	$ 90.92	$ 94.84	$ 88.40												$ 80.77	$ 75.20	$ 75.36
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)	$ 24.23	$ 24.79	$ 26.87													$ 28.02	$ 29.07				$ 26.69			$ 23.41		$ 26.87	$ 33.11	$ 32.08	$ 24.42					$ 63.09							$ 15.79	$ 16.09	$ 15.99
Common Stock, Capital Shares Reserved for Future Issuance													500,000																	250,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				131,702						132,000	0	154,000																			131,702	30,090	117,723	55,572	366	131,702	0	1,092	3,291	1,719
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)				$ 85.80						$ 85.80	$ 0	$ 87.55																			$ 85.80	$ 99.75	$ 84.38		$ 95.24			$ 91.54	$ 83.49	$ 94.50
Stock Issued During Period, Shares, Employee Stock Purchase Plans										2,459,000	825,000	1,283,000																													75,281	85,487	75,718