Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2022	May 31, 2021	May 31, 2022	May 31, 2021	Aug. 31, 2021
Lessor and Lessee, Lease, Description [Line Items]
Operating lease rental revenues	$ 16.0	$ 8.0	$ 47.3	$ 32.1
Finance lease option to extend			options to extend up to 15 years
Car Hire Utilization Arrangements
Lessor and Lessee, Lease, Description [Line Items]
Operating lease rental revenues	3.8	2.8	$ 12.3	10.2
Minimum
Lessor and Lessee, Lease, Description [Line Items]
Sublease period			1 year
Financing lease remaining lease term			1 year
Maximum
Lessor and Lessee, Lease, Description [Line Items]
Sublease period			14 years
Financing lease remaining lease term			76 years
Equipment on Operating Lease
Lessor and Lessee, Lease, Description [Line Items]
Accumulated depreciation	42.5		$ 42.5		$ 34.4
Depreciation expense	$ 5.5	$ 3.3	$ 15.9	$ 10.1