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VESSELS, NET (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) Vessel	Dec. 31, 2014 USD ($) Vessel	Dec. 31, 2013 USD ($)
VESSELS, NET [Abstract]
Number of vessels | Vessel	24	22
Impairment loss on vessel	$ 0	$ 0	$ 0
Schedule of Vessels [Line Items]
Total	1,612,940	1,477,637
Accumulated Depreciation	(650,255)	(567,645)
Vessels, Net	962,685	909,992
Vessels [Member]
Schedule of Vessels [Line Items]
Total	1,530,245	1,406,872
Drydocking [Member]
Schedule of Vessels [Line Items]
Total	$ 82,695	$ 70,765

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Amount before accumulated depreciation of vessels used in the normal conduct of business and not intended for resale.

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Carrying amount at the balance sheet date of vessels used in the normal conduct of business and not intended for resale, net of accumulated depreciation on vessels.

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The number of vessels under the operational management at of the balance sheet date.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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