Accumulated Other Comprehensive Income (Reclassification from AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	Feb. 29, 2020	Feb. 28, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of revenue	$ 5,694,958	$ 5,612,116	$ 12,646,817	$ 11,598,741
Interest expense	46,183	46,160	91,094	88,812
Income before income tax	29,077	100,826	131,717	265,713
Gain (loss) to be reclassified in next 12 months			3,400
Reclassification out of AOCI | Realized losses (gain) on derivative instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income before income tax	(3,548)		3,335
Reclassification out of AOCI | Realized losses (gain) on derivative instruments | Foreign exchange contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of revenue	(3,117)		4,197
Reclassification out of AOCI | Realized losses (gain) on derivative instruments | Interest rate contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense	$ (431)		$ (862)
Reclassification out of AOCI | Realized losses (gains) on derivative instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Income before income tax		3,501		17,686
Reclassification out of AOCI | Realized losses (gains) on derivative instruments | Foreign exchange contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cost of revenue		3,931		18,546
Reclassification out of AOCI | Realized losses (gains) on derivative instruments | Interest rate contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Interest expense		$ (430)		$ (860)