TAXES (Details 3)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011 Scenario, Adjustment [Member]	Dec. 31, 2010 Scenario, Adjustment [Member]
Actual income tax rate	0.30%	(1.00%)	13.50%
Adjustments due to:
Income not subject to U.S. income taxes	31.30%	25.20%	10.50%
State taxes, net of federal benefit	1.80%	0.00%	0.00%
Basis adjustment recognized related to liquidation of OSG America L.P.	0.00%	0.00%	1.40%
Provision for unrecognized tax benefits	(0.60%)	9.80%	11.20%
Other	2.20%	1.00%	(1.60%)
Valuation allowance	0.00%	0.00%	0.00%
U.S. statutory income tax rate	35.00%	35.00%	35.00%

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Effective Income Tax Rate Reconciliation, Other Reconciling Items

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No definition available.

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- Definition

Effective Income Tax Rate Reconciliation Provision for unrecognized tax benefits during the period.

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No definition available.

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

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-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.4-08.(h)(2))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

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-Subparagraph 2

-Article 4

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Name Accounting Standards Codification

-Topic 740

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-Section S99

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-Subparagraph (SAB TOPIC 6.I)

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-Name Statement of Financial Accounting Standard (FAS)

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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