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Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Feb. 28, 2025	Feb. 29, 2024	Feb. 28, 2025	Feb. 29, 2024	Aug. 31, 2024
Lessor and Lessee, Lease, Description [Line Items]
Operating lease option to extend			options to extend up to 8 years
Leasing & Management Services
Lessor and Lessee, Lease, Description [Line Items]
Operating lease rental revenues	$ 35.6	$ 30.5	$ 67.6	$ 58.1
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	Revenue from Contract with Customer, Excluding Assessed Tax
Car Hire Utilization Arrangements
Lessor and Lessee, Lease, Description [Line Items]
Operating lease rental revenues	$ 6.2	$ 5.1	$ 10.5	$ 10.5
Minimum
Lessor and Lessee, Lease, Description [Line Items]
Sublease period			1 year
Opreating lease remaining lease term			1 year
Maximum
Lessor and Lessee, Lease, Description [Line Items]
Sublease period			11 years
Opreating lease remaining lease term			74 years
Equipment on Operating Lease
Lessor and Lessee, Lease, Description [Line Items]
Accumulated depreciation	107.2		$ 107.2		$ 93.4
Depreciation expense	$ 9.5	$ 8.4	$ 18.1	$ 16.2

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Lessor and lessee lease, description.

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Operating Lease Remaining Lease Term.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
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Indicates line item in statement of income or comprehensive income that includes operating lease income.

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-Topic 842
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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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