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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2012 Derivative | Dec. 31, 2011 Derivative | Dec. 31, 2010 | Dec. 31, 2004
Orion Tankers Pool [Abstract] |  |  |  |
Number of tankers withdrawn from pool | 9 |  |  |
Cash and Cash Equivalents [Abstract] |  |  |  |
Original maturities of deposits classified as cash and cash equivalents (in months) | 3M |  |  |
Vessels, Net [Abstract] |  |  |  |
Number of types of vessel | 1 |  |  |
Historical and Average Spot Market Rate | 15 years |  |  |
Improvements amortized over a period (in years) | 25 |  |  |
Impairment Of Long-Lived Assets [Abstract] |  |  |  |
Salvage value of the vessel | $ 9.7 |  |  |
Drydock [Abstract] |  |  |  |
Period when vessels are required to be drydocked, minimum (in months) | 30M |  |  |
Period when vessels are required to be drydocked, maximum (in months) | 60M |  |  |
Deferred Compensation Liability [Abstract] |  |  |  |
Number of individual deferred compensation agreements | 2 |  |  |
Segments [Abstract] |  |  |  |
Number of operating segment | 1 |  |  |
Interest Risk [Abstract] |  |  |  |
Number of derivatives outstanding | 0 | 0 |  |
Geographical Segment [Abstract] |  |  |  |
Total number of vessels | 20 | 17 | 17 | 3
Ballast Tank [Member] |  |  |  |
Vessels, Net [Abstract] |  |  |  |
Improvements amortized over a period (in years) | 8 |  |  |

X
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- Details
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- Details
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X
- Definition The historical and average spot market rate used when estimating daily time charter equivalent for the remaining operating days. + References No definition available. + Details
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- Details
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- Details
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- Definition Number of derivatives outstanding as of the balance sheet date. + References No definition available. + Details
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- Definition The number of individual deferred compensation agreements during the period. + References No definition available. + Details
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- Definition The number of operating segment during the year. + References No definition available. + Details
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- Definition The total number of tankers withdrawn from pool during the period, which may include crude oil tankers and new vessels under construction to be used in the normal conduct of business and not intended for resale. + References No definition available. + Details
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- Definition The number of different types of vessels owned and operated by the Company. + References No definition available. + Details
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- Definition The original maturity, in months, of deposits classified as cash and cash equivalents. + References No definition available. + Details
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- Details
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- Definition The maximum period when the vessels are expected to be drydocked for overhaul repairs and maintenance. + References No definition available. + Details
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- Definition The minimum period when the vessels are expected to be drydocked for overhaul repairs and maintenance. + References No definition available. + Details
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- Definition The total number of vessels during the period, which may include crude oil tankers and new vessels under construction to be used in the normal conduct of business and not intended for resale. + References No definition available. + Details
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- Details
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