Company Inquiry and Restatement (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended			12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012		Dec. 31, 2012	Dec. 31, 2011
Proceeds from Dividends Received	$ 1,207,650			$ 1,194,150
Aggregate Deemed Repatriation Amount	1,489,000
Deferred Tax Liabilities, Tax Deferred Income				103,388
Retained earnings		1,671
Income Tax Expense (Benefit)	(5,835)	528
Deemed Dividend Income				77,000
Taxable Income From Foreign Earnings	76,000			77,000
Increase (Decrease) in Income Taxes		1,875
Increase In Income Taxes Recoverable		21,434
Liability For Uncertain Tax Positions, Noncurrent	18,631	323,003		17,067
Deferred Income Taxes and Other Tax Liabilities, Noncurrent		191,376
Stockholders Equity, Period Increase (Decrease)		535,813
Undistributed earnings of affiliated companies	(6,719)	1,932
Other Comprehensive Income (Loss), Net of Tax	(8,200)	(9,570)
Increase Of Investments In Affiliated Company		23,298
Accumulated Other Comprehensive Loss	(105,581)	(109,737)		(113,781)	(119,307)
Scenario, Adjustment [Member]
Income Tax Expense (Benefit)		1,875	[1]
Undistributed earnings of affiliated companies		172	[2]
Other Comprehensive Income (Loss), Net of Tax		4,111
Accumulated Other Comprehensive Loss		21,627
Internal Revenue Service (IRS) [Member]
Potential Deemed Dividends And Other Adjustments				460,000
Bankruptcy Claims, Amount of Claims Settled				463,013
Osg International, Inc [Member]
Adjustments To Additional Taxable Income				234,853
Aggregate Deemed Repatriation Amount				$ 1,317,500

[1] To adjust for the overstatement in the income tax benefit primarily related to changes in for uncertain tax positions and the after-tax effect of accrued interest related to the reserve for uncertain tax positions.

[2] To adjust undistributed earnings of affiliates for the $172 overstatement in equity in income of affiliated companies resulting from the error in the method used to estimate the credit valuation adjustments associated with the fair valuation of the interest rate swap derivative contracts of certain of the Company's equity method investees.