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Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2021	May 31, 2020	May 31, 2021	May 31, 2020	Aug. 31, 2020
Lessor and Lessee, Lease, Description [Line Items]
Operating lease rental revenues	$ 8.0	$ 9.0	$ 32.1	$ 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	2.8	$ 10.2	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			15 years
Financing lease remaining lease term			77 years
Equipment on Operating Lease
Lessor and Lessee, Lease, Description [Line Items]
Accumulated depreciation	30.5		$ 30.5		$ 33.4
Depreciation expense	$ 3.3	$ 2.6	$ 10.1	$ 9.2

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Lessor and lessee lease, description.

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Operating Lease Remaining Lease Term.

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- Definition

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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- Definition

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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- Definition

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

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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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