Derivative Financial Instruments and Hedging Activities - Schedule of Derivative Instruments, Effect on Earnings (Details) - Designated as Hedging Instrument - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	May 31, 2019	May 31, 2018	May 31, 2019	May 31, 2018
Derivative [Line Items]
Gain (loss) on fair value hedging relationship	$ 0	$ 0	$ 0	$ 0
Interest Expense | Interest rate swap derivatives
Derivative [Line Items]
Gain (loss) on fair value hedging relationship	(8,122)	(231)	(15,129)	(18,118)
Interest Expense | Hedged Item
Derivative [Line Items]
Gain (loss) on fair value hedging relationship	$ 8,122	$ 231	$ 15,129	$ 18,118