Accuracy Of Cost Estimate

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- Definition

Commitments and Contingencies Disclosure [Line Items]

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- Definition

Feasibility and Evaluation Costs

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- Definition

Monitoring Action Time Frame

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- Definition

New data collection period to reflect actual cost prior to final remedy design.

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- Definition

Number Of Sediment Decision Units

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- Definition

Remedial Action Time Frame.

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- Definition

Undiscounted costs for remedial alternatives.

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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)
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
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Amount awarded to other party in judgment or settlement of litigation.

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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.

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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))
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Commitments and Contingencies - Additional Information (Detail)			204 Months Ended
	Jun. 30, 2017 USD ($)	Jan. 06, 2017 USD ($) Segment	Dec. 31, 2016 USD ($)	Feb. 28, 2018 USD ($)	Nov. 30, 2016 USD ($)
Commitments and Contingencies Disclosure [Line Items]
Remedial investigation and feasibility study			$ 110,000,000
Equity method investment, percentage of ownership interest				50.00%
Note receivable				$ 42,500,000
Performance Guarantee
Commitments and Contingencies Disclosure [Line Items]
Letter of credit facility outstanding amount				$ 75,000,000
Portland Harbor Site
Commitments and Contingencies Disclosure [Line Items]
Number of sediment decision units \| Segment		13
Estimated undiscounted cost		$ 1,700,000,000
Period for remedial action		13 years
Period for monitoring		30 years
New data collection period to reflect actual cost prior to final remedy design		2 years
Portland Harbor Site \| Minimum
Commitments and Contingencies Disclosure [Line Items]
Accuracy of cost estimate		(30.00%)
Portland Harbor Site \| Maximum
Commitments and Contingencies Disclosure [Line Items]
Accuracy of cost estimate		50.00%
GBW Railcar Services LLC
Commitments and Contingencies Disclosure [Line Items]
Equity method investment, percentage of ownership interest				50.00%
Amsted-Maxion Cruzeiro
Commitments and Contingencies Disclosure [Line Items]
Note receivable				$ 10,000,000
Greenbrier-Maxion
Commitments and Contingencies Disclosure [Line Items]
Note receivable				$ 9,100,000
Pending Litigation \| Commercial Litigation in a Foreign Jurisdictions
Commitments and Contingencies Disclosure [Line Items]
Adverse judgment					$ 15,000,000
Adverse judgment	$ 10,000,000