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VESSELS, NET (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 USD ($) Vessel | Dec. 31, 2016 USD ($) Vessel | Dec. 31, 2015 USD ($)
VESSELS, NET [Abstract] |  |  |
Number of vessels | Vessel | 30 | 29 |
Property, Plant and Equipment [Line Items] |  |  |
Total | $ 1,889,270 | $ 1,799,193 |
Less Accumulated Depreciation | (842,977) | (741,144) |
Less Impairment Loss on Vessels | (110,480) | 0 |
Vessels, Net | $ 935,813 | 1,058,049 |
Number of vessels delivered to the Company | Vessel | 1 |  |
Number of vessels the company has taken through periodical maintenance survey | Vessel | 10 |  |
Deposits for vessels under construction | $ 0 | (50,130) | $ (64,000)
Number of vessels under construction delivered in 2018 | Vessel | 3 |  |
Total remaining capital commitments | $ 117,000 |  |
Impairment loss on vessels | $ 110,480 | 0 | $ 0
Number of vessels included in write down for impairment loss | Vessel | 10 |  |
Vessels [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Total | $ 1,769,967 | 1,700,040 |
Drydocking [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Total | $ 119,303 | $ 99,153 |

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