Derivatives And Risk Management (Derivative Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Feb. 29, 2012		Aug. 31, 2011
Derivatives, Fair Value [Line Items]
Derivative liabilities (accrued expenses, other payables and long-term liabilities)	$ 7,939	[1]	$ 5,688	[1]
Commodity [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities (accrued expenses, other payables and long-term liabilities) Not Designated as Hedging Instrument, Fair Value	3,751		2,625
Foreign Exchange [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities (accrued expenses, other payables and long-term liabilities) Designated as Hedging Instrument, Fair Value	2,567		805
Derivative liabilities (accrued expenses, other payables and long-term liabilities) Not Designated as Hedging Instrument, Fair Value	$ 1,621		$ 2,258

[1] Derivative assets and liabilities do not include the hedged (underlying) items designated as fair value hedges.