Share-Based Compensation Plans (Details 1) (USD $)	12 Months Ended
	Aug. 31, 2011 Year	Aug. 31, 2010
Schedule of shares subject to options and SARs
Options and SARs, Outstanding, Number Outstanding, Beginning Balance	3,922,016
Options and SARs, Outstanding, Weighted Average Exercise Price, Ending Balance	$ 27.45	$ 23.67
Options and SARs, Granted, Number	112,000
Options and SARs, Granted, Weighted Average Exercise Price	$ 16.83
Options and SARs, Exercised, Number	(854,023)
Options and SARs, Exercised, Weighted Average Exercise Price	$ 8.03
Options and SARs, Forfeited / Expired, Number	(372,495)
Options and SARs, Forfeited, Weighted Average Exercise Price	$ 28.96
Options and SARs, Outstanding, Number Outstanding, Ending Balance	2,807,498
Options and SARs, Outstanding, Weighted Average Remaining Contractual Life (Years)	2.8
Options and SARs, Outstanding, Aggregate Intrinsic Value	$ 94,500
Options and SARs, Exercisable, Number Outstanding	2,639,498
Options and SARs, Exercisable, Weighted Average Exercise Price	$ 28.19
Options and SARs, Exercisable, Weighted Average Remaining Contractual Life (Years)	2.8
Options and SARs, Exercisable, Aggregate Intrinsic Value	$ 94,500