Represents the amount of bankruptcy claim converted into shares of the entity.

No definition available.

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Namespace Prefix:	gnk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the amount of bankruptcy claim to be settled.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the amount to be received in cash settle bankruptcy claim.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Represents the percentage of settlement of bankruptcy claim to be received in cash as percentage of total settlement.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Represents the amounts received as a bankruptcy claim due in past year.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amounts received as a bankruptcy claim due in past two years.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount of bankruptcy claim to be converted into shares of the entity expressed as percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the percentage of bankruptcy claim due that was remitted.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of total cash settlement to be received annually in bankruptcy claim.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents period of Payment plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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

No definition available.

+ Details

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

- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The total amount of other operating income, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

Name:	us-gaap_OtherOperatingIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585

+ Details

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Period Type:	duration

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- Details

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COMMITMENTS AND CONTINGENCIES - Settlements (Details) - USD ($) $ in Thousands				6 Months Ended		12 Months Ended
	Oct. 27, 2016	May 02, 2016	Apr. 08, 2016	Dec. 31, 2014	Jul. 09, 2014	Dec. 31, 2016	Dec. 31, 2015	Feb. 05, 2010
Bankruptcy settlement
Other operating income recognized				$ 530		$ 960	$ 0
Predecessor
Bankruptcy settlement
Other operating income recognized					$ 0
Bankruptcy settlement due \| Samsun
Bankruptcy settlement
Amount of bankruptcy claim to be settled following the rehabilitation process			$ 3,979
Cash to be received to settle bankruptcy claim as percentage of total settlement			26.00%
Cash to be received to settle bankruptcy claim			$ 1,035
Tenure of Payment plan			10 years
Bankruptcy claims settled by conversion into shares of entity (as a percent)			74.00%
Amount Received	$ 777	$ 157
Net present Value			$ 1,035
2012 Bankruptcy claims received				296
2013 Bankruptcy claims received				$ 234
Percentage of bankruptcy claim due remitted				50.00%
Other operating income recognized				$ 530		$ 934	$ 0
Bankruptcy settlement due \| Samsun \| Predecessor
Bankruptcy settlement
Amount of bankruptcy claim to be settled following the rehabilitation process								$ 17,212
Cash to be received to settle bankruptcy claim as percentage of total settlement								34.00%
Cash to be received to settle bankruptcy claim								$ 5,852
Bankruptcy claims settled by conversion into shares of entity (as a percent)								66.00%
Amount of bankruptcy claim settled through conversion into shares of entity								$ 11,360
Bankruptcy settlement due \| Samsun \| Predecessor \| Minimum
Bankruptcy settlement
Percentage of total cash settlement to be received annually								8.00%
Bankruptcy settlement due \| Samsun \| Predecessor \| Maximum
Bankruptcy settlement
Percentage of total cash settlement to be received annually								17.00%