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VOYAGE REVENUES (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disaggregation of Revenue [Abstract] |  |  |  |  |
Total Voyage Revenues | $ 317,220 |  | $ 289,016 |  | $ 297,141
Future Minimum Revenues [Abstract] |  |  |  |  |
Capitalized cost | $ 1,000 |  | 1,100 |  |
Maximum [Member] |  |  |  |  |
Future Minimum Revenues [Abstract] |  |  |  |  |
Term of voyage contract | 1 year |  |  |  |
Spot Charter [Member] |  |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |  |
Total Voyage Revenues | $ 283,007 | [1] | 259,978 | [1] | 257,495
Time Charter [Member] |  |  |  |  |
Disaggregation of Revenue [Abstract] |  |  |  |  |
Total Voyage Revenues | 34,213 |  | $ 29,038 |  | $ 39,646
Future Minimum Revenues [Abstract] |  |  |  |  |
2020 | 27,932 |  |  |  |
2021 | 7,317 |  |  |  |
2022 | 0 |  |  |  |
Future minimum revenues | $ 35,249 |  |  |  |
[1] | Spot charter revenues for 2019 and 2018 are presented in accordance we ASC 606 Revenue from Contracts with Customers. The comparative information for 2017 has not been restated.

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