RELATED PARTY TRANSACTIONS - Other Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Peter C Georgiopoulos And Company LLC \| Office expenses
Related party transactions
Amount of expense incurred on behalf of related parties	$ 9	$ 7	$ 7
Due from related parties	7	4
Genco \| Business, travel, and entertainment costs
Related party transactions
Amount of expense incurred on behalf of related parties		100	100
Due from related parties	0	0
Aegean \| Bunker and lubricating oil purchases
Related party transactions
Bunkers and lubricating oils purchased	2,900	5,200	8,200
Due to related parties	200	1,000
Aegean \| Rent and other expenses
Related party transactions
Amount of expense incurred on behalf of related parties	200	200	200
Due from related parties	0	0
Chemical \| Rent and other expenses
Related party transactions
Amount of expense incurred on behalf of related parties	79	72	$ 60
Due from related parties	$ 2	$ 100

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: 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
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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