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Leases - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Feb. 28, 2022 | Feb. 28, 2021 | Feb. 28, 2022 | Feb. 28, 2021 | Aug. 31, 2021
Lessor and Lessee, Lease, Description [Line Items] |  |  |  |  |
Operating lease rental revenues | $ 16.3 | $ 12.3 | $ 31.3 | $ 24.1 |
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 | 3.9 | 3.8 | $ 8.5 | 7.4 |
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 |  |  | 77 years |  |
Equipment on Operating Lease |  |  |  |  |
Lessor and Lessee, Lease, Description [Line Items] |  |  |  |  |
Accumulated depreciation | 37.6 |  | $ 37.6 |  | $ 34.4
Depreciation expense | $ 5.4 | $ 3.2 | $ 10.5 | $ 6.8 |

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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919372-209981 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123420820&loc=SL77919311-209978 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=124502072&loc=SL77927221-108306 + Details
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