Name:	gnk_CancellationOfProvisionOfTechnicalServicesByServiceReceiverUponChangeOfControlPeriodForTerminationFee
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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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Period Type:	instant

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_
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Balance Type:	na
Period Type:	duration

- Details

Name:	gnk_GeneralInformationLineItems
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Data Type:	xbrli:stringItemType
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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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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
Period Type:	instant

Represents the ownership percentage held in the subsidiary.

No definition available.

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Data Type:	num:percentItemType
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Period Type:	instant

Represents the aggregate voting power held in the subsidiary.

No definition available.

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Data Type:	num:percentItemType
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Represents the threshold of the aggregate percentage of subsidiary's stock owned by parent which is necessary for parent to receive an additional number of subsidiary's Class B shares in future issuances.

No definition available.

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Data Type:	num:percentItemType
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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.

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

Interest rate stated in the contractual 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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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

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Amount per share assigned to the consideration received for shares issued.

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)

-URI http://asc.fasb.org/extlink&oid=6472370&loc=d3e38297-110927

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Data Type:	num:perShareItemType
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Period Type:	duration

Balance held at close of period in number of shares.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 14

-Paragraph Column B

-Article 12

Reference 2: 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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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 Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

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Data Type:	xbrli:monetaryItemType
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Number of new stock issued during the period.

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-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.