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INVESTMENTS (Details) - USD ($) $ in Millions |  | 12 Months Ended
--- | --- | ---
Dec. 11, 2018 | Dec. 31, 2018 | Dec. 31, 2017
Equity Method Investment [Abstract] |  |  |
Impairment of investment |  | $ 2.6 |
NATs share of NAOs total market capitalization |  | $ 4.2 | $ 12.0
Nordic American Offshore Limited [Member] |  |  |
Equity Method Investment [Abstract] |  |  |
Ownership interest |  | 13.55% | 16.10%
Additional equity | $ 5.0 |  |
Transaction recognized in dilution loss | $ 0.6 | $ 4.4 |
Investment value, cost basis |  | 4.2 |
Dividends received |  | 0.3 | $ 1.0
Carrying value of investment |  | $ 4.2 |

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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=114001220&loc=d3e32787-111569 + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
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- Definition Fair value portion of investments accounted under the equity method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=66022186&loc=d3e32014-111567 + Details
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- Definition Dividends received on equity and other investments during the current period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 16 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3337-108585 + Details
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- Definition The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.3(a)) -URI http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263 + Details
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