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VESSELS (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 USD ($) Vessel | Dec. 31, 2018 USD ($) Vessel | Dec. 31, 2017 USD ($)
VESSELS [Abstract] |  |  |  |
Number of vessels | Vessel | 23 | 23 |  |
Residual value | $ 8,000 |  |  |
Estimated useful life | 25 years |  |  |
Vessels [Abstract] |  |  |  |
Total | $ 1,369,567 | $ 1,359,418 |  |
Less Accumulated Depreciation | (469,570) | (405,660) | [1] |
Less Accumulated Impairment Loss on Vessels | 0 | 0 | [2] |
Vessels | 899,997 | 953,758 |  |
Depreciation charges disposed |  | 497,000 |  |
Impairment loss on vessels | $ 0 | 2,168 |  | $ 110,480
Number of vessels the company taken through periodical maintenance survey | Vessel | 3 |  |  |
Number of vessels in drydock for periodical maintenance | Vessel | 2 |  |  |
Vessels [Member] |  |  |  |
Vessels [Abstract] |  |  |  |
Additions | $ 2,531 | 169,446 |  |
Disposals | 0 | (632,326) |  |
Total | 1,307,087 | 1,769,967 |  |
Drydocking [Member] |  |  |  |
Vessels [Abstract] |  |  |  |
Additions | 7,618 | 8,210 |  |
Disposals | 0 | (75,182) |  |
Total | $ 52,331 | $ 119,303 |  |
[1] | Depreciation charges of $497.0 million related to vessels disposed of in 2018 is excluded
[2] | Impairment charges of $2.2 million and $110.5 million related to vessels disposed of in 2018 is excluded

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