RELATED PARTY TRANSACTIONS - Navig8 Pools (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Related party transactions
Revenue from related party	$ 292,975	$ 368,889	$ 149,642
Navig8 Group
Related party transactions
Revenue from related party	293,000	368,900	149,600
Due from related parties	26,300	60,700
Navig8 Group \| VL8 Pool
Related party transactions
Revenue from related party	233,000	239,000	75,900
Due from related parties	18,800	40,900
Navig8 Group \| Suez8 Pool
Related party transactions
Revenue from related party	50,800	103,500	52,400
Due from related parties	6,400	16,100
Navig8 Group \| V8 Pool
Related party transactions
Revenue from related party	9,200	26,400	21,300
Due from related parties	$ 1,100	3,700
VLCC vessels \| VL8 Pool Inc. \| VL8 Pool
Related party transactions
Number of vessels directly admitted to pool \| item	21
Suezmax Vessels \| V8 Pool Inc. \| Suez8 Pool
Related party transactions
Number of vessels directly admitted to pool \| item	6
Navig8 Inc. \| Nave Quasar
Related party transactions
Gross daily rate	$ 26
Revenue share above daily threshold (as a percent)	50.00%
Threshold gross daily rate	$ 30
Amount of expense incurred on behalf of related parties	$ 6	$ 3,100	$ 11,300

Represents daily gross rate per vessel in vessel pool.

No definition available.

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- Definition

Represents the number of vessels directly admitted into pool by the entity.

+ References

No definition available.

+ Details

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- Definition

Represents the percentage of revenue share on earnings above daily threshold from related party transactions.

+ References

No definition available.

+ Details

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- Definition

Represents the threshold of daily gross rate per vessel in vessel pool subject to percentage of profit share.

+ References

No definition available.

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- Definition

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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

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Balance Type:	debit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Details

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- Details

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- Details

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- Details

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