Note 15. Stock-Based Compensation (Detail) - Summary of Stock Option Weighted Average Assumptions Of Employee Stock Options (USD $)	0 Months Ended			3 Months Ended								12 Months Ended
	Jan. 13, 2012	Jan. 14, 2011	Jan. 15, 2010	Aug. 31, 2012	Nov. 30, 2011	Aug. 31, 2011	May 31, 2011	Feb. 28, 2011	Aug. 31, 2010	Feb. 28, 2010	Nov. 30, 2009	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Term structure of risk-free interest rate												0.94%	2.13%	2.54%
Expected life (years)												5 years 156 days	5 years 156 days	5 years 156 days
Term structure of volatility												33.60%	31.10%	35.40%
Dividend yield												1.11%	1.18%	1.42%
Weighted average estimated fair value (in Dollars per share)	$ 24.79	$ 26.87	$ 21.06	$ 33.11	$ 32.08	$ 28.02	$ 23.41	$ 29.07	$ 20.19	$ 21.01	$ 19.99
Weighted average exercise price (in Dollars per share)				$ 90.92	$ 94.84	$ 96.10	$ 103.30	$ 99.78	$ 67.41	$ 63.09	$ 66.46
Employee Stock Purchase Plan Fair Value Determinations [Member] | Minimum [Member]
Term structure of risk-free interest rate												0.13%	0.18%	0.15%
Expected life (years)												7 years 219 days	4 years	4 years
Term structure of volatility												29.00%	23.00%	27.00%
Dividend yield
Weighted average estimated fair value (in Dollars per share)
Employee Stock Purchase Plan Fair Value Determinations [Member] | Maximum [Member]
Term structure of risk-free interest rate												2.41%	1.88%	3.30%
Expected life (years)												9 years 36 days	6 years 6 months	6 years 255 days
Term structure of volatility												36.00%	35.00%	36.00%
Employee Stock Purchase Plan Fair Value Determinations [Member]
Dividend yield												1.16%	1.25%	1.51%
Weighted average estimated fair value (in Dollars per share)												32.34	24.78	20.22
Weighted average exercise price (in Dollars per share)												93.86	89.39	66.35
Fair value as a percentage of exercise price												34.50%	27.70%	30.50%