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Represents the additional shares that the entity has received as a percentage of the number of common shares issued by subsidiary, for maintaining minimum threshold percentage of the aggregate number of outstanding shares of the subsidiary by the entity, directly or indirectly.

No definition available.

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Represents the additional shares that the entity is entitled to receive as a percentage of the number of common shares to be issued in the future by subsidiary if the entity directly or indirectly holds the minimum threshold percentage of the aggregate number of outstanding shares of the subsidiary.

No definition available.

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Namespace Prefix:	gnk_
Data Type:	num:percentItemType
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Represents the notice period for cancellation of provision of technical services by the reporting entity at any time.

No definition available.

Name:	gnk_NoticePeriodForCancellationOfProvisionOfTechnicalServicesByEntity
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Data Type:	xbrli:durationItemType
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Represents the notice period for cancellation of provision of technical services by the service receiver upon change of control of the reporting entity.

No definition available.

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Data Type:	xbrli:durationItemType
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Number of days after notice from trustee the entity is required cure the default of not making the scheduled amortization payment of its Convertible Senior Notes

No definition available.

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Period Type:	duration

The number of days after year end the audited financial statements are to be furnished to certain lenders to allow discussions to continue without the need to file for bankruptcy relief.

No definition available.

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Data Type:	xbrli:durationItemType
Balance Type:	na
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Represents the number of interest rate derivatives previously classified as a long-term liability.

No definition available.

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Data Type:	xbrli:integerItemType
Balance Type:	na
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Represents the ownership interest held by related party.

No definition available.

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Balance Type:	na
Period Type:	instant

Represents the ownership percentage held in the subsidiary.

No definition available.

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The percentage of principal amount outstanding under a Debt Instrument held by Required Supporting Creditors which is needed to terminate the Support Agreement along with mutual written agreement of the Company.

No definition available.

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Data Type:	num:percentItemType
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Period Type:	duration

Represents the aggregate voting power held in the subsidiary.

No definition available.

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Rights offering of equity in the reorganized Company under the proposed plan of reorganization.

No definition available.

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Balance Type:	credit
Period Type:	duration

Represents the initial term of provision of technical service.

No definition available.

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Data Type:	xbrli:durationItemType
Balance Type:	na
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Represents the technical services fee revenue per ship per day for drybulk vessels which includes oversight of crew management, insurance, drydocking, ship operations and financial statement preparation, but do not include chartering services.

No definition available.

Name:	gnk_TechnicalServicesFeeRevenuePerShipPerDay
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Balance Type:	credit
Period Type:	duration

Amount of termination fee payable to Supporting Lenders under the 2007 Credit Facility and Supporting Noteholders if the Support Agreement is terminated under certain circumstances and the Company consummates an alternative transaction.

No definition available.

Name:	gnk_TerminationFee
Namespace Prefix:	gnk_
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Balance Type:	debit
Period Type:	duration

- Details

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Regulation S-X (SX)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

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-Subparagraph (SX 210.5-02.22(a)(1))

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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Amount per share or per unit assigned to the consideration received of equity securities issued for development stage entities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 915

-SubTopic 215

-Section 45

-Paragraph 1

-Subparagraph (b)

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Number of shares of affiliates held for management investment companies.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 6

-Subparagraph (SX 210.12-14.Column B)

-URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611322-123010

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-Name Regulation S-X (SX)

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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

-Topic 210

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-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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-Number 210

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Number of new stock issued during the period.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

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-Name Accounting Standards Codification

-Topic 505

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

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-Article 5

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.