Name:	fro_AssetsPledgedAbstract
Namespace Prefix:	fro_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

This element represents the minimum percentage of bonds issued that have to be redeemed or converted to shares, before the company has the right to redeem the remaining bonds at par plus accrued interest at anytime during the term of the loan.

+ References

No definition available.

+ Details

Name:	fro_BondRedemptionFeatureMinimum
Namespace Prefix:	fro_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the the percentage at which issued bonds will be redeemed as a percentage of the principal unless previously redeemed, converted or purchased and cancelled.

+ References

No definition available.

+ Details

Name:	fro_BondsIssueAndRedemptionFeatures
Namespace Prefix:	fro_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	fro_ConvertibleBondsDue2015Abstract
Namespace Prefix:	fro_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Convertible Debt number of days up to April 14, 2015 to convert at conversion price

+ References

No definition available.

+ Details

Name:	fro_ConvertibleDebtNumberOfDaysUpToApril142015ToConvertAtConversionPrice
Namespace Prefix:	fro_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt Amortized Discount from Bond Buyback Sale

+ References

No definition available.

+ Details

Name:	fro_DebtAmortizedDiscountfromBondBuybackSale
Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt Conversion, Cash Payment

+ References

No definition available.

+ Details

Name:	fro_DebtConversionCashPayment
Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Debt Conversion, Expense due to Inducement Offer

+ References

No definition available.

+ Details

Name:	fro_DebtConversionExpenseduetoInducementOffer
Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt discount effective interest rate

+ References

No definition available.

+ Details

Name:	fro_Debtdiscounteffectiveinterestrate
Namespace Prefix:	fro_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The debt instrument placed on private placement during the period under review.

+ References

No definition available.

+ Details

Name:	fro_DebtInstrumentPlacedOnPrivatePlacement
Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Debt Unamortized Discount Resulting from Bond Buyback Sale

+ References

No definition available.

+ Details

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Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Deconsolidation of subsidiaries

+ References

No definition available.

+ Details

Name:	fro_Deconsolidationofsubsidiaries
Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The per share amount of a dividend declared which adjusts the conversion price.

+ References

No definition available.

+ Details

Name:	fro_DividendsDeclaredAmountPerShareAdjustedForConversion
Namespace Prefix:	fro_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Drawdown of Front Ull & Front Idun loan

+ References

No definition available.

+ Details

Name:	fro_DrawdownofFrontUllFrontIdunloan
Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Front Ull & Front Idun Loan

+ References

No definition available.

+ Details

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Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Minimum Adjustment To Conversion Price, Percent

+ References

No definition available.

+ Details

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Namespace Prefix:	fro_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	fro_MovementInDebtAbstract
Namespace Prefix:	fro_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Notional value of long term debt in subsidiary entity sold

+ References

No definition available.

+ Details

Name:	fro_NotionalValueOfLongTermDebtInSubsidiaryEntitySold
Namespace Prefix:	fro_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the number of shares that may be issued if the bonds were converted at the current conversion price per share.

+ References

No definition available.

+ Details

Name:	fro_NumberOfNewSharesToBeIssued
Namespace Prefix:	fro_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the number of Tranches of Windsor Petroleum Transport Corporation 7.84% term notes purchased on the open market.

+ References

No definition available.

+ Details

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Namespace Prefix:	fro_
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Balance Type:	na
Period Type:	duration

- Definition

Number of Vessels Pledged as Security

+ References

No definition available.

+ Details

Name:	fro_NumberofVesselsPledgedasSecurity
Namespace Prefix:	fro_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Repurchase of debt carrying value

+ References

No definition available.

+ Details

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Namespace Prefix:	fro_
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Balance Type:	credit
Period Type:	duration

- Definition

Repurchase of debt percentage holding

+ References

No definition available.

+ Details

Name:	fro_RepurchaseOfDebtPercentageHolding
Namespace Prefix:	fro_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Repurchase of debt purchase price

+ References

No definition available.

+ Details

Name:	fro_RepurchaseOfDebtPurchasePrice
Namespace Prefix:	fro_
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Balance Type:	credit
Period Type:	duration

- Definition

The percentage of the principal amount being redeemed through the operation of the mandatory sinking funds according to the schedule of sinking fund redemption payments in respect of the 8.04% First Preferred Mortgage Term Notes.

+ References

No definition available.

+ Details

Name:	fro_SinkingFundRedemptionPrice
Namespace Prefix:	fro_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The total carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate and rate subject to change from time to time.

+ References

No definition available.

+ Details

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Namespace Prefix:	fro_
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Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount at the balance sheet date of vessels and other long-lived depreciable physical assets used in the normal conduct of business and not intended for resale, net of accumulated depreciation on vessels and equipments.

+ References

No definition available.

+ Details

Name:	fro_VesselsAndEquipmentNet
Namespace Prefix:	fro_
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Balance Type:	debit
Period Type:	instant

- Definition

Weighted average interest on floating rate debt

+ References

No definition available.

+ Details

Name:	fro_Weightedaverageinterestonfloatingratedebt
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Period Type:	duration

- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 20

-Section 50

-Paragraph 5

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Paragraph 1

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- Definition

Maximum contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

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-Name Regulation S-X (SX)

-Number 210

-Section 02

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- Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Foreign exchange rate used to remeasure amounts denominated in a currency other than functional currency into functional currency.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 30

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521

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- Definition

Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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-Name Regulation S-X (SX)

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Amount of long-term debt, after unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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-Section S99

-Paragraph 1

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-Name Regulation S-X (SX)

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-Section 02

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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-Name Accounting Standards Codification

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-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

Name:	us-gaap_LongTermDebtNoncurrent
Namespace Prefix:	us-gaap_
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- Details

Name:	us-gaap_MaturitiesOfLongTermDebtAbstract
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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

No definition available.

+ Details

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Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

Name:	us-gaap_SharePrice
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DEBT (Details) (USD $)	0 Months Ended	1 Months Ended	12 Months Ended			1 Months Ended			3 Months Ended		1 Months Ended	3 Months Ended		0 Months Ended	2 Months Ended	1 Months Ended	3 Months Ended	1 Months Ended
DEBT (Details) (USD $)	Mar. 26, 2010 D	Oct. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014	Oct. 31, 2013	Mar. 31, 2012	Mar. 31, 2012	Sep. 30, 2014	Jun. 30, 2014	Jun. 30, 2014	Dec. 31, 2014	Jul. 15, 2014	Aug. 31, 2008 tranch	Feb. 28, 2015	Mar. 31, 2015	Jan. 31, 2015	Aug. 25, 2011	May 24, 2011	Mar. 07, 2011	Feb. 22, 2011	Dec. 21, 2010	Sep. 08, 2010	Aug. 27, 2010	Jun. 02, 2010	May 21, 2010
Debt Instrument [Line Items]
Total US Dollar floating rate and fixed rate debt			$ 192,857,000	$ 459,078,000		$ 192,857,000							$ 192,857,000
Current portion of long-term debt			(165,357,000)us-gaap_LongTermDebtCurrent	(22,706,000)us-gaap_LongTermDebtCurrent		(165,357,000)us-gaap_LongTermDebtCurrent							(165,357,000)us-gaap_LongTermDebtCurrent
Long-term debt			27,500,000us-gaap_LongTermDebtNoncurrent	436,372,000us-gaap_LongTermDebtNoncurrent		27,500,000us-gaap_LongTermDebtNoncurrent							27,500,000us-gaap_LongTermDebtNoncurrent
Movement in debt [Roll Forward]
Balance at beginning of period			459,078,000us-gaap_LongTermDebt	483,992,000us-gaap_LongTermDebt	513,513,000us-gaap_LongTermDebt				513,513,000us-gaap_LongTermDebt
Loan repayments			(54,732,000)us-gaap_RepaymentsOfDebt	(21,531,000)us-gaap_RepaymentsOfDebt	(19,521,000)us-gaap_RepaymentsOfDebt
Repurchase of debt carrying value		(17,800,000)fro_RepurchaseOfDebtCarryingValue			10,000,000fro_RepurchaseOfDebtCarryingValue
Notional value of long term debt in subsidiary entity sold				32,019,000
Debt Amortized Discount from Bond Buyback Sale			1,629,000	1,820,000
Balance at end of period			192,857,000us-gaap_LongTermDebt	459,078,000us-gaap_LongTermDebt	483,992,000us-gaap_LongTermDebt	192,857,000us-gaap_LongTermDebt							192,857,000us-gaap_LongTermDebt
Convertible bonds due 2015 [Abstract]
Repurchase of debt purchase price		16,300,000fro_RepurchaseOfDebtPurchasePrice
Debt Conversion, Cash Payment			10,000,000fro_DebtConversionCashPayment
Convertible Debt number of days up to April 14, 2015 to convert at conversion price	10
Maturities of Long-term Debt [Abstract]
2015			165,357,000			165,357,000							165,357,000
2016			2,000,000			2,000,000							2,000,000
2017			25,500,000			25,500,000							25,500,000
2018			0			0							0
2019			0			0							0
Thereafter			0			0							0
Total debt			192,857,000us-gaap_LongTermDebt	459,078,000us-gaap_LongTermDebt	483,992,000us-gaap_LongTermDebt	192,857,000us-gaap_LongTermDebt							192,857,000us-gaap_LongTermDebt
Assets pledged [Abstract]
Vessels, net,			56,624,000fro_VesselsAndEquipmentNet	264,804,000fro_VesselsAndEquipmentNet		56,624,000fro_VesselsAndEquipmentNet							56,624,000fro_VesselsAndEquipmentNet
Vessels by Name [Member]
First Preferred Mortgage Term Notes [Abstract]
Number of Vessels Pledged as Security				6
Assets pledged [Abstract]
Vessels, net,			55,812,000	263,367,000		55,812,000							55,812,000
Vessel [Member]
First Preferred Mortgage Term Notes [Abstract]
Number of Vessels Pledged as Security			1			1							1
Restricted cash and investment [Member]
Assets pledged [Abstract]
Restricted cash and investments			38,560,000	66,249,000		38,560,000							38,560,000
Debt Conversion [Member]
Convertible bonds due 2015 [Abstract]
Debt Conversion, Original Debt, Amount		23,000,000
4.5% convertible bond due 2015
Movement in debt [Roll Forward]
Repurchase of debt carrying value			17,800,000
Convertible bonds due 2015 [Abstract]
Stated interest rate (in hundredths)	4.50%		4.50%			4.50%							4.50%
Debt Conversion, Converted Instrument, Shares Issued		8,251,724				4,744,752
Share Price		$ 1.45	$ 2.62			$ 2.62							$ 2.62
8.04% First Preferred Mortgage Term Notes
First Preferred Mortgage Term Notes [Abstract]
Stated interest rate range, minimum (in hundredths)			7.84%
Stated interest rate range, maximum (in hundredths)			8.04%
First Preferred Mortgage Term Notes due 2021 [Member] \| First Preferred Mortgage Term Notes due 2021 [Member]
First Preferred Mortgage Term Notes [Abstract]
Stated interest rate range, maximum (in hundredths)				7.84%
4.5% convertible bond due 2015
Movement in debt [Roll Forward]
Repurchase of debt carrying value								(10,000,000)
Convertible bonds due 2015 [Abstract]
Repurchase of debt purchase price								5,400,000
Gain (Loss) on repurchase of debt instrument		1,500,000							4,600,000
Repurchase of debt percentage holding		23.50%						4.40%
Debt Conversion, Original Debt, Amount							25,000,000
Debt Conversion, Converted Instrument, Shares Issued							6,474,827
Debt Conversion, Cash Payment		10,000,000				9,600,000	2,250,000
Debt Conversion, Expense due to Inducement Offer			41,100,000				12,700,000
4.5% convertible bond due 2015 \| Debt Conversion [Member]
Convertible bonds due 2015 [Abstract]
Debt Conversion, Original Debt, Amount						22,500,000
4.5% convertible bond due 2015 \| 4.5% convertible bond due 2015
Convertible bonds due 2015 [Abstract]
Debt Conversion, Original Debt, Amount			(45,500,000)	(25,000,000)
US Dollar denominated fixed rate debt [Member] \| 4.5% convertible bond due 2015
Debt Instrument [Line Items]
Total US Dollar floating rate and fixed rate debt			126,700,000	190,000,000		126,700,000							126,700,000
Convertible bonds due 2015 [Abstract]
Stated interest rate (in hundredths)	4.50%		4.50%			4.50%							4.50%
Debt instrument placed on private placement	225,000,000
Convertible, conversion price (in dollars per share)	39.00		$ 36.5567	$ 36.5567		$ 36.5567							$ 36.5567								$ 36.5567			$ 37.0483		$ 38.0895
USD/NOK exchange rate	6.0448
Dividend declared (in dollars per share)																			$ 0.02	$ 0.10		$ 0.10	$ 0.25		$ 0.75		$ 0.75
Minimum adjustment to conversion price, percent																							1.00%
Bond redemption features (in hundredths)	100.00%
Bond redemption feature, minimum (in hundredths)			90.00%
Number of new shares to be issued (in shares)			3,465,849
US Dollar denominated fixed rate debt [Member] \| 8.04% First Preferred Mortgage Term Notes
Debt Instrument [Line Items]
Total US Dollar floating rate and fixed rate debt			36,657,000	83,240,000		36,657,000							36,657,000
Debt Unamortized Discount Resulting from Bond Buyback Sale			0	(10,402,000)		0							0
Convertible bonds due 2015 [Abstract]
Bond redemption features (in hundredths)			100.00%			100.00%							100.00%
First Preferred Mortgage Term Notes [Abstract]
Stated interest rate range, minimum (in hundredths)				7.84%
Stated interest rate range, maximum (in hundredths)				8.04%
US Dollar denominated fixed rate debt [Member] \| First Preferred Mortgage Term Notes due 2019 [Member]
Debt Instrument [Line Items]
Total US Dollar floating rate and fixed rate debt			0	196,240,000		0							0
First Preferred Mortgage Term Notes [Abstract]
Stated interest rate range, maximum (in hundredths)			8.04%
US Dollar denominated fixed rate debt [Member] \| First Preferred Mortgage Notes [Member]
First Preferred Mortgage Term Notes [Abstract]
Sinking fund redemption price (in hundredths)			100.00%			100.00%							100.00%
US Dollar denominated floating rate debt [Member]
Debt Instrument [Line Items]
Total US Dollar floating rate and fixed rate debt			29,500,000	0		29,500,000							29,500,000
Long-term debt						60,000,000
US Dollar denominated floating rate debt [Member] \| Vessel [Member]
Movement in debt [Roll Forward]
Loan draw downs										30,000,000
US Dollar denominated floating rate debt [Member] \| US Dollar denominated floating rate debt [Member]
Debt Instrument [Line Items]
Long-term debt						60,000,000
Movement in debt [Roll Forward]
Weighted average interest on floating rate debt			2.80%
US Dollar denominated floating rate debt [Member] \| US Dollar denominated floating rate debt [Member] \| Vessels by Name [Member]
Debt Instrument [Line Items]
Long-term debt											60,000,000
US Dollar denominated floating rate debt [Member] \| US Dollar denominated floating rate debt [Member] \| Front Ull and Front Idun [Member]
Debt Instrument [Line Items]
Long-term debt												0
Movement in debt [Roll Forward]
Loan draw downs			30,000,000
First Preferred Mortgage Term Notes due 2019 [Member] \| 8.04% First Preferred Mortgage Term Notes
First Preferred Mortgage Term Notes [Abstract]
Stated interest rate range, maximum (in hundredths)			8.04%	8.04%
Windsor Group [Member] \| First Preferred Mortgage Term Notes due 2021 [Member]
Movement in debt [Roll Forward]
Debt Amortized Discount from Bond Buyback Sale													(8,800,000)
Deconsolidation of subsidiaries			(179,818,000)
Windsor Group [Member] \| First Preferred Mortgage Term Notes due 2021 [Member] \| First Preferred Mortgage Term Notes due 2021 [Member]
Movement in debt [Roll Forward]
Deconsolidation of subsidiaries														(179,800,000)
International Tankers Corporation Ltd [Member] \| 8.04% First Preferred Mortgage Term Notes
Debt Instrument [Line Items]
Debt Unamortized Discount Resulting from Bond Buyback Sale				(12,200,000)
Movement in debt [Roll Forward]
Notional value of long term debt in subsidiary entity sold				32,000,000
Debt Amortized Discount from Bond Buyback Sale			(1,600,000)
First Preferred Mortgage Term Notes [Abstract]
Number of tranches of term notes purchased															3
Proceeds from Issuance of Debt				19,800,000
Debt discount effective interest rate			7.84%
Stated interest rate range, minimum (in hundredths)															7.84%
Reported Value Measurement [Member]
Debt Instrument [Line Items]
Total US Dollar floating rate and fixed rate debt			29,500,000	0		29,500,000							29,500,000
Movement in debt [Roll Forward]
Debt Amortized Discount from Bond Buyback Sale				(12,222,000)
Subsequent Event [Member]
Movement in debt [Roll Forward]
Repurchase of debt carrying value																(33,300,000)
Subsequent Event [Member] \| 4.5% convertible bond due 2015
Convertible bonds due 2015 [Abstract]
Gain (Loss) on repurchase of debt instrument																	300,000
Subsequent Event [Member] \| US Dollar denominated floating rate debt [Member] \| Vessel [Member]
Movement in debt [Roll Forward]
Loan draw downs																	30,000,000	30,000,000
Subsequent Event [Member] \| US Dollar denominated floating rate debt [Member] \| US Dollar denominated floating rate debt [Member] \| Vessels by Name [Member]
Debt Instrument [Line Items]
Long-term debt																		60,000,000
Subsequent Event [Member] \| International Tankers Corporation Ltd [Member] \| 8.04% First Preferred Mortgage Term Notes
Movement in debt [Roll Forward]
Loan repayments																		$ (36,700,000)