Represents the minimum cash required per vessel mortgaged under this facility.

No definition available.

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Represents the cash and cash equivalents and undrawn amount available for working capital required be maintained under the terms of the credit facilities' covenants.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Represents the consolidated net worth threshold amount calculated as per the terms of the credit facilities' covenants.

+ References

No definition available.

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- Definition

Represents the percentage of the value of any subsequent primary equity offerings that is used in the calculation of consolidated net worth threshold amount as per the terms of the credit facilities' covenants.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Represents the aggregate fair value of the mortgaged vessels to be maintained as a percentage of aggregate outstanding principal amount after August 30, 2016 as per the terms of the credit facilities' covenants.

+ References

No definition available.

+ Details

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- Definition

Represents maximum ratio of financial indebtedness to total assets under the terms of the credit facility leverage covenant.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Represents the number of quarterly installments in which the line of credit facility shall be repaid.

+ References

No definition available.

+ Details

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- Definition

Represents the required payment amount under the line of credit facility due on final maturity date.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of payment made towards outstanding debt during the period.

+ References

No definition available.

+ Details

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Balance Type:	debit
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- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.19(b),22(b))
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-Section 02
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- Definition

Amount of the required periodic payments of both interest and principal.

+ References

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- Definition

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

+ References

+ Details

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- Definition

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

+ 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.

+ References

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

No definition available.

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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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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.

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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.

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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.

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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.

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DEBT (Details 6) $ in Thousands				12 Months Ended
DEBT (Details 6) $ in Thousands	Feb. 10, 2016 USD ($)	Sep. 04, 2013	Aug. 30, 2013 USD ($) item	Dec. 31, 2015 USD ($)	Jul. 14, 2015 USD ($)	Dec. 31, 2014 USD ($)
Line of Credit Facility
Debt classified as current liability				$ 588,434		$ 34,324
Secured Debt \| $22 Million Term Loan Facility
Line of Credit Facility
Maximum borrowing capacity				22,000	$ 22,000	22,000
Remaining borrowing capacity				0
Long-term debt				18,625		$ 20,125
Debt classified as current liability				18,625
Prepayment of outstanding debt	$ 220
Repayment of the outstanding debt
2016				1,500
2017				1,500
2018				1,500
2019				14,125
Long-term Line of Credit, Total				$ 18,625
Remedy period available to post additional collateral or reduce the amount of the revolving loans and/or letters of credit outstanding				30 days
Collateral security maintenance test (as a percent)				110.00%	110.00%
Maintained Aggregate fair market value of the mortgaged vessels as a percentage of aggregate outstanding principal amount (as a percent)				108.70%
Prepayment of the outstanding indebtedness	$ 220
Secured Debt \| $22 Million Term Loan Facility \| Baltic Fox and Baltic Hare
Line of Credit Facility
Minimum cash required to be maintained by each collateralized vessel				$ 500
Cash and cash equivalents and undrawn amount available for working capital required to be maintained				750
Predecessor \| Secured Debt \| $22 Million Term Loan Facility
Line of Credit Facility
Maximum borrowing capacity			$ 22,000	$ 22,000
Term of facilities		6 years
Commitment fee on unused daily average unutilized commitment (as a percent)			1.00%
Number of quarterly installments \| item			23
Amount of periodic payment			$ 375
Final payment amount			$ 13,375
Maximum ratio of financial indebtedness to total assets (as a percent)			70.00%
Consolidated net worth threshold, base amount			$ 786,360
Consolidated net worth threshold, percentage of the value of any subsequent primary equity offerings (as a percent)			50.00%
Aggregate fair market value of the mortgaged vessels as a percentage of amount outstanding (as a percent)			130.00%
Aggregate fair market value of the mortgaged vessels as a percentage of amount outstanding after August 30, 2016 (as a percent)			135.00%
Repayment of the outstanding debt
Period after latest vessel delivery date for first periodic repayment			3 months
Predecessor \| Secured Debt \| $22 Million Term Loan Facility \| LIBOR
Line of Credit Facility
Reference rate for interest payable			three-month LIBOR
Applicable margin over reference rate (as a percent)			3.35%