Number of vessels included in write down for impairment loss.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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ACQUISITIONS (Details) $ in Thousands		12 Months Ended
ACQUISITIONS (Details) $ in Thousands	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