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Related Party Transactions - Additional Information (Detail) - Axis LLC - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
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Feb. 28, 2022 | Feb. 28, 2021 | Feb. 28, 2022 | Feb. 28, 2021
Related Party Transaction [Line Items] |  |  |  |
Percentage of ownership in entity | 41.90% |  | 41.90% |
Railcar Components |  |  |  |
Related Party Transaction [Line Items] |  |  |  |
Purchases of goods from related party | $ 3.3 | $ 2.2 | $ 6.1 | $ 6.0

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + 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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- Details
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