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VESSELS, NET (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 USD ($) Vessel | Dec. 31, 2015 USD ($) Vessel | Dec. 31, 2014 USD ($)
VESSELS, NET [Abstract] |  |  |
Number of vessels | Vessel | 29 | 24 |
Impairment loss on vessel | $ 0 | $ 0 | $ 0
Schedule of Vessels [Line Items] |  |  |
Total | 1,799,193 | 1,612,940 |
Accumulated Depreciation | (741,144) | (650,255) |
Vessels, Net | 1,058,049 | 962,685 |
Vessels [Member] |  |  |
Schedule of Vessels [Line Items] |  |  |
Total | 1,700,040 | 1,530,245 |
Drydocking [Member] |  |  |
Schedule of Vessels [Line Items] |  |  |
Total | $ 99,153 | $ 82,695 |

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