v3.10.0.1

Major Customers and Concentration Of Risks (Details)	12 Months Ended
	Dec. 31, 2018 Employee
Concentration Risk [Line Items]
Number of employees	1,868
Refined Products Segment [Member]
Concentration Risk [Line Items]
Number of employees	948
Crude Oil Pipeline and Terminals Segment [Member]
Concentration Risk [Line Items]
Number of employees	160
Marine Storage Segment [Member]
Concentration Risk [Line Items]
Number of employees	201
Customer Concentration Risk [Member]
Concentration Risk [Line Items]
Customer Concentration Risk, Benchmark Percentage	10.00%
Unionized Employees Concentration Risk [Member] | Refined Products Segment [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	24.00%
Unionized Employees Concentration Risk [Member] | Crude Oil Pipeline and Terminals Segment [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	0.00%
Unionized Employees Concentration Risk [Member] | Marine Storage Segment [Member]
Concentration Risk [Line Items]
Concentration Risk, Percentage	14.00%

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Number of persons employed by the Entity

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Customer Concentration Risk, Benchmark Percentage

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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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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