Revenue Recognition - Additional information (Detail1) $ in Millions	Aug. 31, 2026 USD ($)
Rail Cars [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected revenue to be recognized	$ 979.7
Rail Cars [Member] \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-09-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected revenue to be recognized period	12 months
Fleet management
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected revenue to be recognized	$ 92.0
Fleet management \| Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-09-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected revenue to be recognized period	5 years
Manufacturing \| Rail Cars [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected revenue to be recognized	$ 1,208.1

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (a)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

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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.

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- Definition

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

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