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v3.8.0.1

INVESTMENTS (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 31, 2017 | Jun. 30, 2014 | Nov. 18, 2013 | Nov. 30, 2015 | Mar. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Jul. 20, 2017 | Jun. 16, 2017 | Dec. 31, 2007
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Private equity placement issued amount |  |  |  |  |  | $ 103,748 | $ 120,069 |  |  |  |  |
Shares as dividend-in-kind (in shares) |  |  |  |  |  |  |  |  | 699,802 |  |  |
Company acquired additional shares in open market (in shares) |  |  |  |  |  |  |  |  | 488,216 |  |  |
Company acquired additional shares in private transaction (in shares) |  |  |  | 1,521,300 |  |  |  |  |  |  |  |
Dividends paid (in dollars per share) |  |  |  |  |  | $ 0.53 | $ 1.37 | $ 1.38 |  |  |  |
Cash value (in dollars per share) |  |  |  |  |  |  |  |  |  |  | $ 30 | $ 115
Loss on investments |  |  |  |  |  | $ (8,435) | $ (46,642) | $ (2,462) |  |  |  |
Impairment of investment |  |  |  |  |  | 0 | 37,300 |  |  |  |  |
NATs share of NAOs total market capitalization |  |  |  |  |  | $ 12,000 | $ 16,600 |  |  |  |  |
Nordic American Offshore Limited [Member] |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Private equity placement participation |  |  |  |  | $ 10,000 |  |  |  |  |  |  |
Shares as dividend-in-kind (in shares) | 4,024,745 |  |  |  |  |  |  |  |  |  |  |
Ownership interest |  |  |  |  | 22.60% | 16.10% | 29.10% |  |  |  |  |
Transaction recognized in dilution loss |  |  |  |  | $ 2,600 |  |  |  |  |  |  |
Dividends paid (in dollars per share) | $ 0.10 |  |  |  |  |  |  |  |  |  |  |
Number of shareholders held common shares (in shares) | 250 |  |  |  |  |  |  |  |  |  |  |
Number of shareholders received common shares (in shares) | 1 |  |  |  |  |  |  |  |  |  |  |
Common shares received per common share (in shares) | 24.4 |  |  |  |  |  |  |  |  |  |  |
Cash value (in dollars per share) | $ 0.05 |  |  |  |  |  |  |  |  |  |  |
Closing price (in dollars per share) |  |  |  |  |  |  |  |  |  | $ 1.22 |  |
Maximum number of shares held by shareholder to receive cash dividend (in shares) | 249 |  |  |  |  |  |  |  |  |  |  |
Cash dividend received per common share (in dollars per share) | $ 0.05 |  |  |  |  |  |  |  |  |  |  |
Loss on investments | $ 700 |  |  |  |  |  |  |  |  |  |  |
Carrying value of investment |  |  |  |  |  | $ 12,200 |  |  |  |  |  |
Financial Position [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Current assets |  |  |  |  |  | 37,076 | $ 7,909 |  |  |  |  |
Noncurrent assets |  |  |  |  |  | 350,635 | 366,945 |  |  |  |  |
Total Assets |  |  |  |  |  | 387,711 | 374,854 |  |  |  |  |
Current liabilities |  |  |  |  |  | 2,809 | 4,089 |  |  |  |  |
Noncurrent liabilities |  |  |  |  |  | 136,629 | 136,568 |  |  |  |  |
Total Shareholders' Equity |  |  |  |  |  | 248,273 | 234,196 |  |  |  |  |
Total liabilities and equity |  |  |  |  |  | 387,711 | 374,854 |  |  |  |  |
NATs share of NAOs equity |  |  |  |  |  | 40,000 | 68,100 |  |  |  |  |
Summarized Statement of Operations information [Abstract] |  |  |  |  |  |  |  |  |  |  |  |
Operating Revenues |  |  |  |  |  | 17,895 | 17,697 | 36,372 |  |  |  |
Net Operating (Loss) Income |  |  |  |  |  | (26,068) | (28,543) | (8,372) |  |  |  |
Net (Loss) Income |  |  |  |  |  | (29,326) | (32,151) | (10,844) |  |  |  |
NATs portion of NAOs Net (Loss) Income |  |  |  |  |  | (5,100) | (9,300) | $ (2,500) |  |  |  |
Dividends received |  |  |  |  |  | $ 1,000 | $ 1,700 |  |  |  |  |
Nordic American Offshore Limited [Member] | Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Private equity placement issued amount |  |  | $ 250,000 |  |  |  |  |  |  |  |  |
Private equity placement participation |  |  | $ 65,000 |  |  |  |  |  |  |  |  |
Private equity placement participation (in shares) |  |  | 4,333,566 |  |  |  |  |  |  |  |  |
Nordic American Offshore Limited [Member] | IPO [Member] |  |  |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Shares acquired (in shares) |  | 375,000 |  |  |  |  |  |  |  |  |  |
Cost of shares acquired |  | $ 5,600 |  |  |  |  |  |  |  |  |  |

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- Definition The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721683-107760 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
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