Derivative Instruments - Effects of Cash Flow Hedges Included in Statements of Operations (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Feb. 28, 2022	Feb. 28, 2021	Feb. 28, 2022	Feb. 28, 2021
Derivative [Line Items]
Revenue	$ 682.8	$ 295.6	$ 1,233.5	$ 698.6
Cost of revenue	628.0	278.0	1,131.1	640.3
Interest and foreign exchange	11.8	9.6	24.4	20.7
Sales
Derivative [Line Items]
Amount of gain (loss) on cash flow hedge activity	(0.2)	(0.4)	(0.4)	(0.6)
Cost of Sales
Derivative [Line Items]
Amount of gain (loss) on cash flow hedge activity				(0.1)
Interest and Foreign Exchange
Derivative [Line Items]
Amount of gain (loss) on cash flow hedge activity	$ (1.3)	$ (1.3)	$ (2.6)	$ (2.6)