Amount recognized from sale of railcars accounted for under equity method accounting.

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Percentage of deferred revenue and margin from sale.

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Percentage of recognized revenue and margin from sale.

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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.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

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- Definition

The cash inflow from sale of machinery and equipment.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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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Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period.

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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.

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Related Party Transactions - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016	Aug. 20, 2018	Jun. 30, 2017	May 31, 2017	Apr. 30, 2017	Aug. 31, 2015
Related Party Transaction [Line Items]
Carrying amount of investment in unconsolidated affiliates	$ 6.1
Percentage of recognized revenue and margin from sale	60.00%
Percentage of deferred revenue and margin from sale	40.00%
Revenue recognize from railcars sold	$ 48.0
Related party expenses	0.5	$ 0.5	$ 0.8
Leasing Warehouse
Related Party Transaction [Line Items]
Revenue recognize from railcars sold	$ 16.0
Greenbrier
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest	40.00%				40.00%
GBW Railcar Services LLC
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest	50.00%			50.00%				50.00%
Related party transaction other revenue	$ 5.0	5.0	5.0
Sale of wheel sets and components	16.5	18.3	28.5
Related party expenses	$ 0.4	$ 1.0	$ 1.3
GBW Railcar Services LLC \| Watco Companies LLC
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest								50.00%
Amsted-Maxion Cruzeiro
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest	24.50%					24.50%	19.50%
Note receivable	$ 10.0
Greenbrier-Maxion
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest	60.00%					60.00%	19.50%
Note receivable	$ 7.2