VESSELS, DEFERRED DRYDOCK AND OTHER PROPERTY (Details Textual) (USD $) In Thousands, unless otherwise specified	1 Months Ended					2 Months Ended	3 Months Ended		12 Months Ended			3 Months Ended		3 Months Ended	12 Months Ended	3 Months Ended	1 Months Ended		3 Months Ended		12 Months Ended												12 Months Ended				1 Months Ended				12 Months Ended		12 Months Ended
	Oct. 31, 2011	Nov. 30, 2010	Jun. 30, 2010 Vessels	Mar. 31, 2010	Mar. 13, 2009	Dec. 31, 2012	Dec. 31, 2012	Sep. 30, 2010	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2010 International Product Carriers Segment [Member]	Dec. 31, 2012 Handysize Product Carrier Vessel [Member]	Sep. 30, 2010 Us Flag [Member]	Dec. 31, 2011 Us Flag [Member]	Dec. 31, 2012 International Crude Tankers Segment [Member] Vessels	Dec. 31, 2010 International Crude Tankers Segment [Member] Aframaxes Vessel [Member]	Mar. 13, 2009 Bender Shipbuilding and Repair Company Incorporated [Member]	Mar. 31, 2009 Bender Shipbuilding and Repair Company Incorporated [Member]	Jun. 30, 2010 Vessels [Member]	Dec. 31, 2012 Vessels [Member]	Dec. 31, 2011 Vessels [Member]	Dec. 31, 2010 Vessels [Member]	Dec. 31, 2009 Vessels [Member]	Dec. 31, 2012 Vessels [Member] International Crude Tankers Segment [Member]	Dec. 31, 2011 Vessels [Member] International Crude Tankers Segment [Member]	Dec. 31, 2012 Vessels [Member] International Crude Tankers Segment [Member] Very Large Crude Carrier Vessel [Member]		Dec. 31, 2011 Vessels [Member] International Crude Tankers Segment [Member] Very Large Crude Carrier Vessel [Member]	Dec. 31, 2012 Vessels [Member] International Crude Tankers Segment [Member] Aframaxes Vessel [Member]		Dec. 31, 2011 Vessels [Member] International Crude Tankers Segment [Member] Aframaxes Vessel [Member]	Dec. 31, 2012 Vessels [Member] International Crude Tankers Segment [Member] Securities Pledged as Collateral [Member] Very Large Crude Carrier Vessel [Member] Vessels	Dec. 31, 2012 Vessels [Member] International Crude Tankers Segment [Member] Securities Pledged as Collateral [Member] Aframaxes Vessel [Member] Vessels	Dec. 31, 2012 Vessels [Member] International Crude Tankers Segment [Member] Securities Pledged as Collateral [Member] Handysize Product Carrier Vessel [Member] Vessels	Dec. 31, 2012 Vessels [Member] International Crude Tankers Segment [Member] Securities Pledged as Collateral [Member] Panamax Product Carrier Vessel [Member] Vessels	Apr. 30, 2011 Articulated Tug Barge Vessel [Member] Contracts	Mar. 31, 2010 Articulated Tug Barge Vessel [Member] Contract	Sep. 30, 2011 Tug Boat Vessel [Member] Vessels	Jun. 30, 2011 Tug Boat Vessel [Member] Vessels	Dec. 31, 2012 Tug Boat Vessel [Member]	Dec. 31, 2012 Capital Addition Purchase Commitments [Member] Contract	Dec. 31, 2012 Capital Addition Purchase Commitments [Member] Aframaxes Vessel [Member] Contract
Commitments for vessels to be wholly owned																																										$ 41,724
Number of vessels completed																																					1	1	1	1
Number of vessels under contract for construction or purchase																																										2	2
Scheduled delivery of vessels under contract																																									June and September 2011		from the third quarter of 2013 to the first quarter of 2014
Loss on write-down of vessels and intangible assets			25,176	3,607					279,382	0	28,783									12,730
Number Of Impaired Assets Held For Use			8
Impaired Long-Lived Assets Held and Used, Asset Description			(i) two single-hulled International Flag Aframaxes engaged in lightering in the U.S. Gulf, (ii) four single-hulled U.S. Flag vessels, (iii) an older double-hulled U.S. Flag tanker with an inefficient gas turbine engine and (iv) a 1981-built U.S. Flag lightering ATB. The write-downs were the result of difficulties experienced in employing single-hulled vessels and changes in requirements for the Delaware Bay lightering business.
Vessels Sold During Period																						between July 2010 and October 2011
Payment Of Cash Up On Contract Termination					14,000
Significant Acquisitions and Disposals, Acquisition Costs or Sale Proceeds					48,737
Loss on Contract Termination					24,484
Gain Loss On Disposal and Impairment Of Property and Equipment																					588	3,400
Property, Plant, and Equipment, Additional Disclosures									the Company completed construction of a VLCC and an International Flag Handysize Product Carrier.	the Company completed construction of a U.S. Flag ATB, two International Flag Panamax Product Carriers, one VLCC, an International Flag Handysize Product Carrier and two tug boats.	the Company completed construction of one VLCC, two International Flag Handysize Product Carriers and one ATB. In addition, OSG purchased one U.S. Flag Product Carrier upon its delivery from a shipyard.
Significant Acquisitions and Disposals, Description																			In early 2009, OSG began negotiations with Bender Shipbuilding & Repair Co., Inc. (Bender) to terminate the construction agreements covering the six ATBs and two tug boats due to the following: (1) repeated delays in vessel delivery dates from the original contract delivery dates, (2) Benders request for substantial price increases on all contracted vessels and (3) OSGs concern about Benders ability to complete the ATBs and tug boats within contract terms, including Benders lack of performance under such agreements and its financial condition.
Significant Acquisitions and Disposals, Terms																		(1) pay and/or reimburse Bender for the costs associated with positioning the units for transportation to the alternative shipyards and certain other material and labor costs related to construction of the units, (2) assume certain specified obligations related to construction of the units and (3) render a payment of $14,000 to a third party for the release of priority liens on the vessels being transferred to the Company.
Lease Term												5 years
Assets held for sale delivered to buyers	0	one of its single-hulled U.S. Flag Tankers						two U.S. Flag Tankers (one single-hulled and one double-hulled)		two remaining single-hulled U.S. Flag Tankers (one of which was classified as held for sale on the December 31, 2010 consolidated balance sheet) and the remaining chartered-in single-hulled International Flag Aframax in which it had a residual interest to buyers.							one of the chartered-in single-hulled International Flag Aframaxes
Gain (Loss) on Disposition of Property	1,464					(98)	8,078		(271,359)	2,060	161			679
Gain (Loss) on Sale of Other Assets								2,300		4,583				1,162	2,117
Vessels and other property, less accumulated depreciation						2,837,288	2,837,288		2,837,288	3,226,923											2,716,557	2,957,789	2,358,968	2,046,993	1,240,847	1,261,056	711,827	[1]	669,336	210,626	[2]	257,272	486,103	133,433	284,802	284,802
Number Of Vessels																15																	5	3	5	2
Long Lived Assets Held-for-sale, Impairment Charge						278,345	278,345		278,345				94,288																												1,037
Reduction In Deferred Drydock Costs									$ 608

[1] Includes five VLCCs that are pledged as collateral under secured term loans due through 2023, as discussed in Note 11, “Debt,” with an aggregate net carrying value of $486,103.

[2] Includes three Aframaxes that are pledged as collateral under secured term loans due through 2023, as discussed in Note 11, Debt, with an aggregate carrying value of $133,433.