This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(12))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(10))
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(13)(f))
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EQUITY INVESTMENTS - Equity Investments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jan. 31, 2017
Equity investments
Total earnings from equity investments	$ 9,232	$ 2,901	$ 22,710	$ 8,459
VTTI B.V.
Equity investments
Ownership percentage	50.00%		50.00%		50.00%
Global Marine Terminals \| VTTI B.V.
Equity investments
Total earnings from equity investments	$ 6,396	0	$ 15,111	0
Domestic Pipelines & Terminals \| West Shore Pipe Line Company
Equity investments
Total earnings from equity investments	1,772	1,784	4,913	5,680
Domestic Pipelines & Terminals \| Muskegon Pipeline LLC
Equity investments
Total earnings from equity investments	501	544	1,303	1,340
Domestic Pipelines & Terminals \| Transport4, LLC
Equity investments
Total earnings from equity investments	206	204	650	577
Domestic Pipelines & Terminals \| South Portland Terminal LLC
Equity investments
Total earnings from equity investments	$ 357	$ 369	$ 733	$ 862