Employee Stock Option And Retirement Plans (Change In The Actual Financial Performance Levels) (Details) (USD $) In Thousands, unless otherwise specified		12 Months Ended								1 Months Ended
	Aug. 31, 2011	Aug. 31, 2011 Financial Performance Level One [Member]		Aug. 31, 2011 Financial Performance Level Two [Member]		Aug. 31, 2011 Financial Performance Level Three [Member]		Aug. 31, 2011 Financial Performance Level Four [Member]		Oct. 31, 2009 October 2009 Annual Employee Performance Based Option Grant Review [Member]	Nov. 30, 2010 November 2010 Annual Employee Performance Based Option Grant Review [Member]
Employee Stock Option And Retirement Plans [Line Items]
Vesting Percentage		0.00%		20.00%		60.00%		100.00%		100.00%
Total Unamortized Stock-based Compensation Expense at August 31, 2011	$ 44,300	$ 0		$ 2,268		$ 6,804		$ 11,340			$ 2,300
One-time Adjustment		(760)	[1]	0	[1]	1,520	[1]	3,040	[1]
Average Remaining Quarterly Expense to be Recognized		$ 0		$ 136		$ 408		$ 680

[1] Amounts represent the one-time cumulative adjustment to be recorded for the November 2010 performance-based option grant if there had been a change in the vesting percentage as of August 31, 2011. The one-time cumulative adjustment increments each quarter by approximately the amount stated in the average remaining quarterly expense to be recognized column.