Accounts Payable and Accrued Liabilities - Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Millions	Nov. 30, 2021	Aug. 31, 2021	Nov. 30, 2020	Aug. 31, 2020
Payables and Accruals [Abstract]
Trade payables	$ 262.3	$ 265.1
Other accrued liabilities	93.0	109.1
Operating lease liabilities	45.0	42.6
Accrued payroll and related liabilities	112.6	125.1
Accrued warranty	27.5	27.9	$ 45.7	$ 45.2
Accounts payable and accrued liabilities	$ 540.4	$ 569.8