Revenue Recognition - Summary of Estimated Revenue Related to Performance Obligations (Detail) $ in Millions	Feb. 29, 2020 USD ($)
Railcar sales
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue type 1	$ 900.0
Services
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue type 1	140.1
Other
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue type 1	43.6
Manufacturing | Railcar sales
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue type 1	2,698.1
Manufacturing | Marine
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue type 1	58.8
Manufacturing | Railcars for Syndication
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue type 1	$ 261.5	[1]

[1] Not a performance obligation as defined in Topic 606: Contracts with Customers