Summary of Significant Accounting Policies (Details) (USD $)	9 Months Ended
	May 31, 2012	Aug. 31, 2011
Summary of Significant Accounting Policies [Abstract]
Number of Days Used To Determine Short Term Highly Liquid Investments Treatment As Cash Equivalents	90 days
Book Overdrafts	$ 35,000,000	$ 40,000,000
Customer Issued Letters Of Credit	40,000,000	90,000,000
Cash, FDIC Insured Amount	$ 250,000