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Represents the aggregate fair value of the mortgaged vessels to be maintained as a percentage of aggregate outstanding principal amount as per the terms of the credit facilities' covenants.

No definition available.

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Represents the aggregate fair value of the mortgaged vessels actual as a percentage of aggregate outstanding principal amount as per the terms of the credit facilities' covenants.

No definition available.

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Represents the percentage of facility fee on the average daily outstanding principal amount of the loans outstanding.

No definition available.

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Represents the minimum cash balance per vessel required to be maintained for vessels owned under the credit facility.

No definition available.

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Represents the period after latest vessel delivery date for first periodic repayment of the line of credit facility.

No definition available.

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Represents the maximum delivered cost per vessel allowed under the credit facility expected to be financed using term loans.

No definition available.

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Represents the minimum contract period for future time charter contracts required to be secured by liens.

No definition available.

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Number of single term loans for finance requirement.

No definition available.

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Number of unencumbered assets adding as additional collateral to cover the shortfall of fair value of mortgaged assets.

No definition available.

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Represents the number of vessels expected to be acquired by financing through term loans.

No definition available.

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Represents the number of vessels mortgaged by the entity as collateral in support of agreements.

No definition available.

Name:	gnk_NumberOfVesselsMortgaged
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Represents percentage of Amount aggregate outstanding term loan facility due per installment.

No definition available.

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Represents the remedy period available to post additional collateral or reduce the amount of the revolving loans and/or letters of credit outstanding under the terms of the credit facilities' covenants.

No definition available.

Name:	gnk_RemedyPeriodAvailableToPostAdditionalCollateralOrReduceAmountOfRevolvingLoansOrLettersOfCreditOutstanding
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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

No definition available.

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The average effective interest rate during the reporting period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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- References

No definition available.

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When presenting a range of interest rates, the highest effective rate for funds borrowed under the debt agreement as of the balance sheet date.

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When presenting a range of interest rates, the lowest effective rate for funds borrowed under the debt agreement as of the balance sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

No definition available.

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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.

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

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-Section S99

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-Subparagraph (SX 210.5-02.22)

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-Name Accounting Standards Codification

-Topic 944

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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

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-Glossary Financing Activities

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Subparagraph (SX 210.4-08.(f))

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