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Period referring customer relationship maintained by some of the manufacturing and refining customers.

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Number of single customers who account for more than 10 percent of segment revenues.

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Refers to the number of top distributors of off-highway engines.

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No definition available.

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Percentage of costal revenue from movement of products under term contracts.

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No definition available.

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Percentage of inland revenue from movement of products under term contracts.

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No definition available.

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- Definition

Validity period of contract with customers.

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No definition available.

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- Definition

Relationship term maintained by entity with customers.

+ References

No definition available.

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- Definition

Term of the guarantee or each group of financial instruments used to support performance by the company and its subsidiaries in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248

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- References

No definition available.

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Contingencies and Commitments, Certain Significant Risks and Uncertainties (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) Customers Distributor	Dec. 31, 2018 Customers	Dec. 31, 2017 Customers
Guaranties [Abstract]
Issued guaranties	$ 22,804,000
Maximum [Member]
Guaranties [Abstract]
Guarantor obligations, expiration period	2 years
Performance Bonds [Member]
Guaranties [Abstract]
Issued guaranties	$ 11,564,000
Marine Transportation [Member]
Certain Significant Risks and Uncertainties [Abstract]
Percentage of inland revenue	65.00%
Marine Transportation [Member] \| Minimum [Member]
Certain Significant Risks and Uncertainties [Abstract]
Range of renewal options under term contracts	1 year
Marine Transportation [Member] \| Maximum [Member]
Certain Significant Risks and Uncertainties [Abstract]
Range of renewal options under term contracts	3 years
Marine Transportation [Member] \| Customers [Member]
Certain Significant Risks and Uncertainties [Abstract]
Percentage of costal revenue	80.00%
Customer relationship period	40 years
Number of single customers accounting more than 10% of segment revenue \| Customers	0	0	0
Distribution and Services [Member]
Certain Significant Risks and Uncertainties [Abstract]
Number of off-highway top distributors \| Distributor	5
Distribution and Services [Member] \| Minimum [Member]
Certain Significant Risks and Uncertainties [Abstract]
Services segment's relationship term	50 years
Distribution and Services [Member] \| Customers [Member]
Certain Significant Risks and Uncertainties [Abstract]
Number of single customers accounting more than 10% of segment revenue \| Customers	0	0	0
Letters Of Credit [Member]
Guaranties [Abstract]
Issued guaranties	$ 11,240,000