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Revenue Recognition - Summary of Estimated Revenue Related to Performance Obligations (Detail) $ in Millions | Aug. 31, 2021 USD ($)
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Railcar sales |  |
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items] |  |
Revenue type 1 | $ 1,400.0 |
Services |  |
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items] |  |
Revenue type 1 | 132.8 |
Other |  |
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items] |  |
Revenue type 1 | 72.3 |
Manufacturing | Railcar sales |  |
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items] |  |
Revenue type 1 | 2,354.1 |
Manufacturing | Marine |  |
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items] |  |
Revenue type 1 | 70.3 |
Manufacturing | Railcars intended for syndication |  |
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items] |  |
Revenue type 1 | $ 292.5 | [1]
[1] | Not a performance obligation as defined in Topic 606

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- Definition Amount of transaction price allocated to performance obligation that has not been recognized as revenue. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130556-203045 + Details
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