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VOYAGE REVENUES (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disaggregation of Revenue [Abstract] |  |  |  |
Total Voyage Revenues | $ 289,016 |  | $ 297,141 | $ 357,451
Spot Charter [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Total Voyage Revenues | 259,978 | [1] | 257,978 | 325,314
Time Charter [Member] |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |
Total Voyage Revenues | 29,038 |  | $ 39,646 | $ 32,137
Future Minimum Revenues [Abstract] |  |  |  |
2019 | 18,315 |  |  |
2020 | 7,686 |  |  |
2021 | 7,315 |  |  |
Future minimum revenues | $ 33,316 |  |  |
[1] | Spot charter revenues for 2018 is presented in accordance we ASC 606 Revenue from Contracts with Customers. The comparative information has not been restated.

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- Definition Amount of lease payments to be received by lessor in third fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919396-209981 + Details
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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045 + Details
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