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VOYAGE REVENUES (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disaggregation of Revenue [Abstract] |  |  |
Voyage Revenues | $ 354,619 | $ 317,220 | $ 289,016
Future Minimum Revenues [Abstract] |  |  |
Capitalized cost | $ 400 | 1,000 |
Maximum [Member] |  |  |
Future Minimum Revenues [Abstract] |  |  |
Term of voyage contract | 1 year |  |
Spot Charter [Member] |  |  |
Disaggregation of Revenue [Abstract] |  |  |
Voyage Revenues | $ 274,217 | 283,007 | 259,978
Time Charter [Member] |  |  |
Disaggregation of Revenue [Abstract] |  |  |
Voyage Revenues | 80,402 | $ 34,213 | $ 29,038
Future Minimum Revenues [Abstract] |  |  |
2021 | 8,395 |  |
2022 | 0 |  |
2023 | 0 |  |
Total Future Minimum Revenues | $ 8,395 |  |

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