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

No definition available.

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

- Definition

Represents the amounts received under banckruptcy claims.

+ References

No definition available.

+ Details

Name:	gnk_BanckruptcyClaimsReceived
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

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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
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

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

- Definition

Represents the amounts received as a banckruptcy claim due in past twelve months.

+ 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

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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

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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
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- Details

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- Details

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- Details

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- Details

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Data Type:	na
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- Details

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COMMITMENTS AND CONTINGENCIES (Details 2) - USD ($) $ in Thousands		6 Months Ended		12 Months Ended
	Oct. 04, 2013	Dec. 31, 2014	Jul. 09, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 05, 2010
Bankruptcy settlement
Other operating income recognized		$ 530
Predecessor
Bankruptcy settlement
Other operating income recognized			$ 0		$ 121	$ 265
Samsun
Bankruptcy settlement
Other operating income recognized		$ 530
Samsun \| Predecessor
Bankruptcy settlement
Percentage of bankruptcy claim due remitted						50.00%
Banckruptcy claims received					0	$ 263
Other operating income recognized				$ 530	0	263
Korea Line Corporation
Bankruptcy settlement
Other operating income recognized				$ 0
Korea Line Corporation \| Predecessor
Bankruptcy settlement
Other operating income recognized					$ 21	2
Settlement Payment	$ 21					$ 2
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
Percentage of bankruptcy claim due remitted				50.00%
2013 Banckruptcy claims received				$ 234
2012 Banckruptcy claims received				$ 296
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%