Number of railcars sold, scrapped or transferred.

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- Definition

Number of related party railcars purchased.

+ References

No definition available.

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- Definition

Percentage of deferred revenue and margin from sale.

+ References

No definition available.

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- Definition

Percentage of recognized revenue and margin from sale.

+ References

No definition available.

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- Definition

Profit Sharing Agreement Amount Paid

+ References

No definition available.

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- Definition

Value of railcars.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The cash inflow from sale of machinery and equipment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(k)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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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

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.

+ References

No definition available.

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Related Party Transactions - Additional Information (Detail) $ in Millions	1 Months Ended	12 Months Ended
	Sep. 30, 2015 USD ($) Vehicle	Aug. 31, 2017 USD ($) Vehicle	Aug. 31, 2016 USD ($)	Aug. 31, 2015 USD ($)	Jun. 30, 2017	May 31, 2017	Apr. 30, 2017	Feb. 28, 2017 USD ($)	Nov. 30, 2016 USD ($)	Apr. 30, 2016 USD ($) Vehicle
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest		50.00%
Carrying amount of investment in unconsolidated affiliates		$ 7.0
Sale of railcars		$ 130.0
Percentage of recognized revenue and margin from sale		60.00%
Percentage of deferred revenue and margin from sale		40.00%
Note receivable		$ 36.5
Related party expenses		$ 0.5	$ 0.8	$ 0.5
Number of railcars sold, scrapped or transferred \| Vehicle		3,885
Greenbrier
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest		40.00%			40.00%
Third Party
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest					60.00%
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								$ 3.6	$ 4.5
GBW Railcar Services LLC
Related Party Transaction [Line Items]
Equity method investment, percentage of ownership interest		50.00%		50.00%
Sale of railcars		$ 18.3	28.5	$ 25.4
Note receivable		36.5
Related party transaction other revenue		4.9	4.9	4.9
Related party expenses		$ 1.0	$ 1.3	$ 2.4
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