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 received as percentage of total cash 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 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 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

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

- 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

Represents the current settlement amount receivable in cash.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnk_
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

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

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- Details

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- Details

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COMMITMENTS AND CONTINGENCIES (Details 2) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 30, 2013	Dec. 30, 2012	Feb. 05, 2010
Bankruptcy settlement
Other operating income recognized	$ 296
Bankruptcy settlement due \| Samsun
Bankruptcy settlement
Percentage of bankruptcy claim due remitted	50.00%
Other operating income recognized	$ 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
Percentage of bankruptcy claim due remitted			50.00%
Bankruptcy Claims Amount Of Payments Due Remitted		$ 0	$ 263
Amount due to be paid in cash				$ 468	$ 527
Total payment due from entity as a percentage of approved cash settlement				8.00%	9.00%
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%