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Lease Commitments - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2022	Aug. 31, 2021	Aug. 31, 2020
Lessor and Lessee, Lease, Description [Line Items]
Accumulated depreciation	$ 596.7	$ 556.1
Depreciation expense	$ 70.7	75.3	$ 86.6
Finance lease option to extend	options to extend up to 15 years
Leasing & Management Services
Lessor and Lessee, Lease, Description [Line Items]
Operating lease rental revenues	$ 66.8	$ 69.4	$ 38.7
Operating Lease, Lease Income, Statement of Income or Comprehensive Income [Extensible Enumeration]	Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax
Car Hire Utilization Arrangements
Lessor and Lessee, Lease, Description [Line Items]
Operating lease rental revenues	$ 18.1	$ 17.1	$ 11.2
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	$ 48.6	34.4	33.4
Depreciation expense	$ 22.0	$ 13.8	$ 11.6

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Lessor and lessee lease, description.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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