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Related Party Transactions - Additional Information (Detail) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
May 31, 2021 | May 31, 2020 | May 31, 2021 | May 31, 2020
Related Party Transaction [Line Items] |  |  |  |
Carrying amount of investment in unconsolidated affiliates | $ 3,200,000 |  | $ 3,200,000 |
Axis LLC |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Percentage of ownership in entity | 41.90% |  | 41.90% |
Axis LLC | Railcar Components |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Purchases of goods from related party | $ 3,300,000 | $ 4,300,000 | $ 10,000,000.0 | $ 11,500,000
Greenbrier |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Percentage of ownership in entity | 40.00% |  | 40.00% |
Greenbrier | Leasing Warehouse |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Revenue recognize from railcars sold |  |  | $ 0 | $ 0

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party. + References No definition available. + Details
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- Definition Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07.1(c)) -URI http://asc.fasb.org/extlink&oid=120401555&loc=SL114874292-224272 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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- Details
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