Represents the line items for significant accounting policies schedule.

No definition available.

Name:	gnk_SummaryOfSignificantAccountingPoliciesLineItems
Namespace Prefix:	gnk_
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Period Type:	duration

- Definition

Indicates (true false) whether practical expedient is elected to account for lease component and nonlease component as single lease component.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL117410129-209981

+ Details

Name:	us-gaap_LeasePracticalExpedientLessorSingleLeaseComponent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

+ Details

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

- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977

+ Details

Name:	us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:
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Period Type:

- Details

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Period Type:

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2019
Summary of Significant Accounting Policies
Operating Lease, Right-of-use asset	$ 5,495	$ 6,882
Operating Lease, Liability	$ 8,061
Lease, Practical Expedient, Lessor Single Lease Component	true
ASU 2016-02 \| Cumulative Effect Period Of Adoption Adjustment
Summary of Significant Accounting Policies
Operating Lease, Right-of-use asset			$ 9,710
Operating Lease, Liability			$ 13,095