FAIR VALUE MEASUREMENTS (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Nonrecurring Basis [Member] \| Vessels [Member]
Fair Value Measurements [Abstract]
Fair market value of assets		$ 12,550
Income Approach [Member]
Fair Value Measurements [Abstract]
Estimated fair value of outstanding debt	$ 1,369,932	984,017
Carrying amount of debt	$ 1,399,931	$ 992,406

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Name Accounting Standards Codification
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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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-Topic 942
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-Paragraph 1
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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

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- References

No definition available.

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