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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 USD ($) Vessel Agreement Segment Subsidiary Customer Charter | Dec. 31, 2015 USD ($) Customer Charter | Dec. 31, 2014 USD ($) Customer | Nov. 12, 2015
Basis of Accounting [Abstract] |  |  |  |  |
Long-Term Debt | [1] | $ 442,820 | $ 324,568 |  |
Other Non-current Assets |  | $ 10,487 | 10,474 |  |
Cash and Cash Equivalents [Abstract] |  |  |  |  |
Original maturities of deposits classified as cash and cash equivalents |  | 3 months |  |  |
Accounts Receivable [Abstract] |  |  |  |  |
Allowance for doubtful balances |  | $ 150,000 | 0 |  |
Vessels, Net [Abstract] |  |  |  |  |
Number of types of vessel | Vessel |  | 1 |  |  |
Historical and average spot market rate |  | 15 years |  |  |
Estimate useful life of vessel |  | 25 years |  |  |
Impairment on vessels |  | $ 0 | 0 | $ 0 |
Impairment Of Long-Lived Assets [Abstract] |  |  |  |  |
Salvage value of the vessel |  | $ 9,000 |  |  |
Drydock [Abstract] |  |  |  |  |
Period when vessels are required to be drydocked, minimum |  | 30 months |  |  |
Period when vessels are required to be drydocked, maximum |  | 60 months |  |  |
Deferred Compensation Liability [Abstract] |  |  |  |  |
Number of individual deferred compensation agreements | Agreement |  | 2 |  |  |
Defined Benefit Plan [Abstract] |  |  |  |  |
Net liability |  | $ 100 | $ 200 |  |
Segment Information [Abstract] |  |  |  |  |
Number of operating segment | Segment |  | 1 |  |  |
Income Taxes [Abstract] |  |  |  |  |
Statutory rate of corporate earnings |  | 0.00% |  |  |
Number of wholly owned subsidiaries | Subsidiary |  | 2 |  |  |
Income tax rate for wholly-owned subsidiaries in Norway |  | 25.00% | 27.00% | 27.00% |
Income tax expense |  | $ (102) | $ (96) | $ (47) |
Concentration Risk [Line Items] |  |  |  |  |
Accounts receivable, net |  | $ 18,100 | 28,600 |  |
Scenario, Previously Reported [Member] |  |  |  |  |
Basis of Accounting [Abstract] |  |  |  |  |
Long-Term Debt |  |  | 330,000 |  |
Other Non-current Assets |  |  | $ 15,900 |  |
Ballast Tank [Member] |  |  |  |  |
Vessels, Net [Abstract] |  |  |  |  |
Improvements amortized over a period |  | 8 years |  |  |
Nordic American Offshore Limited [Member] |  |  |  |  |
Principles of Consolidation [Line Items] |  |  |  |  |
Percentage of ownership interest |  |  |  |  | 29.10%
Accounts Receivable [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration of credit risk percentage |  | 44.00% | 43.00% |  |
Number of charterers accounted for outstanding amount | Charter |  | 3 | 2 |  |
Accounts Receivable [Member] | Customer One [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration of credit risk percentage |  | 16.00% | 20.00% |  |
Accounts Receivable [Member] | Customer Two [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration of credit risk percentage |  | 16.00% | 21.00% |  |
Accounts Receivable [Member] | Customer Three [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration of credit risk percentage |  | 12.00% |  |  |
Revenues [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Number of customers accounted for total revenues | Customer |  | 1 | 2 | 2 |
Concentration of credit risk percentage |  | 32.00% | 42.00% | 40.00% |
Revenues [Member] | Customer One [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration of credit risk percentage |  |  | 30.00% | 29.00% |
Revenues [Member] | Customer Two [Member] |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration of credit risk percentage |  |  | 12.00% | 11.00% |
[1] | Long-Term Debt consists of outstanding amounts on the Credit Facility less unamortized deferred financing cost. Outstanding amounts on the Credit Facility were $447,000 and $330,000 as of December 31, 2016 and 2015, respectively. Please see note 2 to these Consolidated Financial Statements describing the effects of the accounting principle change covering the deferred financing cost.

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