Segment Information - Reconciliation of Earnings (Loss) from Operations to Earnings (Loss) Before Income Tax and Earnings from Unconsolidated Affiliates (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2022	May 31, 2021	May 31, 2022	May 31, 2021
Segment Reporting [Abstract]
Earnings (loss) from operations	$ 19.6	$ 25.7	$ 56.6	$ (2.1)
Interest and foreign exchange	14.9	10.2	39.3	30.9
Net loss on extinguishment of debt		4.8		4.8
Earnings (loss) before income tax and earnings from unconsolidated affiliates	$ 4.7	$ 10.7	$ 17.3	$ (37.8)