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

No definition available.

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

- Definition

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

+ 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 of bankruptcy claim to be settled.

+ References

No definition available.

+ Details

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

- Definition

Represents the amount of bankruptcy claim due which was remitted.

+ 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 to be received in cash settle bankruptcy claim.

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

+ References

No definition available.

+ Details

Name:	gnk_BankruptcyClaimsAmountToBeReceivedInCashToSettleClaimsAsPercentageOfTotalSettlement
Namespace Prefix:	gnk_
Data Type:	num:percentItemType
Balance Type:	na
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 amount of bankruptcy claim 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

The fair value of shares received in lieu of cash in the payment of a settlement.

+ References

No definition available.

+ Details

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

- Definition

Share received pursuant to the rehabilitation plan approved by the South Korean courts.

+ References

No definition available.

+ Details

Name:	gnk_NumberOfSharesReceivedRelatedToRehabilitationPlan
Namespace Prefix:	gnk_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Final revised rehabilitation plan approved by the South Korean courts which resulted in a settlement payment.

+ References

No definition available.

+ Details

Name:	gnk_SettlementPayment
Namespace Prefix:	gnk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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

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

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_PredecessorMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	dei_LegalEntityAxis=gnk_SamsunLogixCorporationMember
Namespace Prefix:
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- Details

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Data Type:	na
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- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_OtherIncomeMember
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- Details

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Data Type:	na
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- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
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COMMITMENTS AND CONTINGENCIES (Details 2) - USD ($) $ in Thousands			6 Months Ended			12 Months Ended
	Jul. 09, 2014	Oct. 04, 2013	Dec. 31, 2014	Jul. 09, 2014	Jun. 30, 2014	Dec. 31, 2015	Dec. 31, 2013	Feb. 05, 2010
Bankruptcy settlement
Other operating income recognized			$ 530			$ 0
Predecessor
Bankruptcy settlement
Other operating income recognized				$ 0			$ 121
Samsun
Bankruptcy settlement
Other operating income recognized			530
Korea Line Corporation
Bankruptcy settlement
Other operating income recognized						0
Korea Line Corporation \| Predecessor
Bankruptcy settlement
Other operating income recognized				$ 0			$ 21
Settlement Payment		$ 21
Number of shares received related to the rehabilitation plan (in shares)		3,355					3,355
Korea Line Corporation \| Predecessor \| Other Income
Bankruptcy settlement
Fair value of shares received		$ 100					$ 100
Bankruptcy settlement due \| Samsun
Bankruptcy settlement
2012 Bankruptcy claims received			296
2013 Bankruptcy claims received			$ 234
Percentage of bankruptcy claim due remitted			50.00%
Other operating income recognized			$ 530
Bankruptcy Claims Amount Of Payments Due Remitted						$ 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 Claims Amount Of Payments Due Remitted	$ 0				$ 0		$ 0
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%