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ACQUISITIONS (Details) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Jan. 10, 2013 USD ($) | Dec. 31, 2017 USD ($) Vessel Unit | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Business Acquisition [Line Items] |  |  |  |
Goodwill recognized |  | $ 0 | $ 18,979 |
Impairment loss on goodwill |  | $ 18,979 | $ 0 | $ 0
Number of reporting units | Unit |  | 1 |  |
Number of vessels included in write down for impairment loss | Vessel |  | 10 |  |
Scandic American Shipping Ltd [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Purchase price | $ 33,300 |  |  |
Common shares paid | 18,100 |  |  |
Cash consideration | 8,000 |  |  |
Payable to seller | 7,200 |  |  |
Goodwill recognized | $ 19,000 |  |  |

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