Share-based Compensation (Shares Subject to Options and SARs Excluding the Cash Component) (Details) (Options and SARs excluding cash component [Member], USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Aug. 31, 2012
Options and SARs excluding cash component [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and SARs, outstanding, number outstanding, beginning balance	2,807,498
Options and SARs, granted, number	828,463
Options and SARs, exercised, number	(361,478)
Options and SARs, forfeited / expired, number	(343,991)
Options and SARs, outstanding, number outstanding, ending balance	2,930,492
Options and SARs, exercisable, number outstanding	2,099,547
Options and SARs, outstanding, weighted average exercise price, beginning balance	$ 27.45
Options and SARs, granted, weighted average exercise price	$ 11.63
Options and SARs, exercised, weighted average exercise price	$ 12.34
Options and SARs, forfeited / expired, weighted average exercise price	$ 27.78
Options and SARs, outstanding, weighted average exercise price, ending balance	$ 24.81
Options and SARs, exercisable, weighted average exercise price	$ 29.90
Options and SARs, outstanding, weighted average remaining contractual life (years)	3 years 3 months 11 days
Options and SARs, exercisable, weighted average remaining contractual life (years)	2 years 1 month 6 days
Options and SARs, outstanding, aggregated intrinsic value	$ 1,104,590
Options and SARs, exercisable, aggregated intrinsic value	$ 223,246