Derivative Financial Instruments and Hedging Activities - Pretax Gains (Losses) On Derivatives Not Accounted For As Hedging Instruments (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	3 Months Ended
	Nov. 30, 2018	Nov. 30, 2017
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ 10,347	$ 40,925
Commodity derivatives | Cost of goods sold
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(6,448)	32,917
Foreign currency derivatives | Cost of goods sold
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	16,056	6,766
Foreign currency derivatives | Selling, General and Administrative Expenses [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(832)	(495)
Interest rate derivatives | Interest Expense
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	0	(1)
Embedded Derivative Financial Instruments [Member] | Other Income [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ 1,571	$ 1,738