Segment Information - Reconciliation of Earnings (Loss) from Operations to Earnings (Loss) Before Income Tax and Earnings (Loss) from Unconsolidated Affiliates (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Feb. 28, 2022	Feb. 28, 2021	Feb. 28, 2022	Feb. 28, 2021
Segment Reporting [Abstract]
Earnings (loss) from operations	$ 25.2	$ (25.7)	$ 37.0	$ (27.8)
Interest and foreign exchange	11.8	9.6	24.4	20.7
Earnings (loss) before income tax and earnings (loss) from unconsolidated affiliates	$ 13.4	$ (35.3)	$ 12.6	$ (48.5)