Represents the number customers of the entity from which revenue was earned.

No definition available.

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- Definition

Represents the number of financial institutions with which the entity maintains its cash and cash equivalents.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

Represents the number of external customers from which the entity generated 10 percent or more of revenues.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

+ References

No definition available.

+ Details

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

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478785/954-310-50-2

+ Details

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Period Type:	duration

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-42

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-Publisher FASB
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+ Details

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- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Data Type:	na
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- Details

Name:	srt_MajorCustomersAxis=gnk_OldendorffCarriersAndSubsidiariesMember
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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentration Risk (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) customer Institution	Dec. 31, 2023 customer Institution	Dec. 31, 2022 customer
Concentration Risk [Line Items]
Number of financial institutions with which the entity maintains its cash and cash equivalents \| Institution	7	8
Cash insured by financial institutions \| $	$ 0
Voyage Revenues \| Customer Concentration Risk
Concentration Risk [Line Items]
Number of customers	129	110	123
Major Customers	2	2	0
Voyage Revenues \| Customer Concentration Risk \| Rio Tinto Shipping (Asia) Pte. Ltd
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)		16.10%
Voyage Revenues \| Customer Concentration Risk \| ST Shipping and Transport Pte. Ltd
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	11.00%
Voyage Revenues \| Customer Concentration Risk \| Oldendorff Carriers and its subsidiaries
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	10.70%	10.90%