Represents the minimum prepayment amount to have the lien released on the vessel.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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 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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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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Namespace Prefix:	gnk_
Data Type:	xbrli:integerItemType
Balance Type:	na
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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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Represents the period after last drawdown date for first periodic repayment of the line of credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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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Data Type:	num:percentItemType
Balance Type:	na
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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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Data Type:	xbrli:stringItemType
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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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Data Type:	xbrli:stringItemType
Balance Type:	na
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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
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	credit
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- Definition

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

+ References

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Balance Type:	debit
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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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Data Type:	num:percentItemType
Balance Type:	na
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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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-Name Accounting Standards Codification
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-SubTopic 210
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-Section 02
-Paragraph 20, 22
-Article 5

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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DEBT - $44M Term Loan (Details) - Secured Debt - $44 Million Term Loan Facility $ in Thousands	Dec. 23, 2013 USD ($)	Dec. 03, 2013 USD ($) item	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Line of Credit Facility
Maximum borrowing capacity				$ 44,000
Minimum cash balance required per vessel owned		$ 750
Long-term debt			$ 0	$ 37,916
Baltic Tiger and Baltic Lion
Line of Credit Facility
Minimum cash required to be maintained by each collateralized vessel		1,000
Predecessor
Line of Credit Facility
Maximum borrowing capacity		$ 44,000
Commitment fee on unused daily average unutilized commitment (as a percent)		0.75%
Number of quarterly installments \| item		23
Amount of periodic payment		$ 688
Period after last drawdown date for first periodic repayment		3 months
Final payment amount		$ 28,188
Amount of prepayments to have liens released		$ 18,000
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%
Collateral security maintenance test (as a percent)		125.00%
Predecessor \| LIBOR
Line of Credit Facility
Reference rate for interest payable		three-month LIBOR
Applicable margin over reference rate (as a percent)		3.35%
Predecessor \| Baltic Tiger
Line of Credit Facility
Drawdowns during the period	$ 21,400
Predecessor \| Baltic Lion
Line of Credit Facility
Drawdowns during the period	$ 22,600