Description of business and basis of preparation (Details) (USD $)	6 Months Ended
Jun. 30, 2013 carrier entities	Feb. 01, 2008
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of affiliated entities which reporting entity acts as agent	2
Number of large crude carriers acquired and constructed	2
Frontline's distribution of ITCL' common shares (in hundredths)		17.53%
Annual management fee paid by the Owners to Frontline	$ 50,000
Termination notice period of management agreement between the Owners and Frontline	30 days

The termination notice period under an existing management agreement.

No definition available.

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The management fee paid as part of agreement for services rendered pertaining to administrative, management and advisory services provided.

No definition available.

The number of affiliated entities for which reporting entity acts as agent.

No definition available.

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Represents the number of crude carriers which are acquired and constructed.

No definition available.

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The percentage of distribution of common shares in a intermediary holding company to common shareholders of the parent.

No definition available.

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