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Related Party Transactions - Frontline, and Seatankers Transactions - Additional Information (Detail) - Frontline [Member] - Ship Finance International Ltd VIEs [Member] - USD ($) $ in Millions | 6 Months Ended
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Jun. 30, 2018 | Jun. 30, 2017
Related Party Transaction [Line Items] |  |
Related party expense |  | $ 1.5
Net income | $ 1.1 |

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- Definition Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 + Details
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- Definition Reflects the sum of all other revenue and income realized from sales and other transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party during the period. + References No definition available. + Details
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