Related Party Transactions - Additional Information (Detail) $ in Millions	1 Months Ended	3 Months Ended	15 Months Ended
Sep. 30, 2015 USD ($) Vehicle	Nov. 30, 2016 USD ($) Vehicle	Nov. 30, 2016 USD ($) Vehicle	Apr. 30, 2010 USD ($) Vehicle
Related Party Transaction [Line Items]
Number of railcars sold \| Vehicle		176	3,582
Sale of railcars		$ 1.8	$ 169.0
Number of railcars sold and recognized \| Vehicle		3,193	3,193
Revenue recognize from railcars sold			$ 161.2
Deferred revenue on railcars sold			$ 7.8
Deferred revenue, number of railcars sold \| Vehicle		389	389
Number of railcars to be sold or disposed \| Vehicle		303	303
WL Ross & Co., LLC (WL Ross)
Related Party Transaction [Line Items]
Number of related party railcars purchased \| Vehicle	3,885			4,000
Value of railcars	$ 148.0			$ 256.0
Related party fee	$ 1.0
Profit sharing agreement, amount paid		$ 4.5	$ 4.5
Accrued profit sharing		$ 3.6	$ 3.6

Accrued Profit Sharing Current

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- Definition

Number of Rail Cars

+ References

No definition available.

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- Definition

Number of Rail Cars Sold

+ References

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- Definition

Number of railcars sold and recognized.

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- Definition

Number Of Railcars To Be Sold Or Disposed

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- Definition

Number of related party railcars purchased.

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- Definition

Profit Sharing Agreement Amount Paid

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- Definition

Value of railcars.

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No definition available.

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- Definition

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
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- Definition

The cash inflow from sale of machinery and equipment.

+ References

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- Definition

Direct costs arising from transactions with related parties who are not affiliates or joint Ventures. These costs are categorized as cost of goods sold.

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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.

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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

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