Derivative Financial Instruments and Hedging Activities - Derivative Assets and Liabilities Not Designated as Hedging Instruments (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	12 Months Ended
	Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2018
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ (97,022)	$ 131,091	$ 139,967
Commodity derivatives | Cost of goods sold
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	89,248	125,323	162,321
Foreign exchange derivatives | Cost of goods sold
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(184,692)	4,228	(26,010)
Foreign exchange derivatives | Marketing, general and administrative expenses
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(2,986)	(1,229)	596
Interest rate derivatives | Interest expense
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	(1,226)	0	(1)
Embedded derivative asset | Other income
Derivative [Line Items]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net	$ 2,634	$ 2,769	$ 3,061