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The capitalized liability related to an existing below-market time charter that is acquired with a vessel purchase which is amortized as an increase in voyage revenue over the remaining term of the existing charter.

No definition available.

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The capitalized current asset related to an existing below-market time charter that is acquired with a vessel purchase which is amortized as an increase in voyage revenue over the remaining term of the existing charter.

No definition available.

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Represents the number of vessels committed to be acquired by the entity under purchase agreement.

No definition available.

Name:	gnk_NumberOfVesselsCommittedToBeAcquiredUnderPurchaseAgreement
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Represents the number of vessels purchased under option to be acquired by the entity under purchase agreement.

No definition available.

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Represents the number of vessels to be acquired by the entity under purchase agreement.

No definition available.

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Payment made, of which was held in escrow account, and released after the settlement of transaction.

No definition available.

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The value paid for each vessel purchased.

No definition available.

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Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment in the future.

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 210.5-02.17)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

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Amount of interest capitalized during the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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The amount of previously reported deferred or unearned revenue that was recognized as revenue during the period. For cash flows, this element primarily pertains to amortization of deferred credits on long-term arrangements. As a noncash item, it is deducted from net income when calculating cash provided by or used in operations using the indirect method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 13.A.4(a).Q1)

-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 13

-Section A

-Subsection 1

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The value of all consideration given or received by the Entity in the significant acquisition or disposal.

No definition available.

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Name:	us-gaap_SignificantAcquisitionsAndDisposalsLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	dei_LegalEntityAxis=gnk_BalticTradingLimitedMember
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Name:	gnk_VesselsByNameAxis=gnk_BalticWaspMember
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Name:	gnk_VesselsByNameAxis=gnk_GencoBourgogneGencoMuseAndGencoSpiritMember
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