Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	May 31, 2020	May 31, 2020	Aug. 31, 2019
Lessor and Lessee, Lease, Description [Line Items]
Operating lease rental revenues	$ 9.0	$ 30.2
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	2.8	$ 9.3
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		9 years
Financing lease remaining lease term		78 years
Equipment on Operating Lease
Lessor and Lessee, Lease, Description [Line Items]
Accumulated depreciation	31.1	$ 31.1	$ 44.2
Depreciation expense	$ 2.6	$ 9.2