INTEREST RATE SWAP AGREEMENTS (Details 2) (Interest rate contracts, Predecessor, USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Jul. 09, 2014 item
Impact of derivative instruments and their location within Condensed Consolidated Statement of Operations
Number of vessels mortgaged		35gnk_NumberOfVesselsMortgaged
Aggregate amount of collateral		$ 100,000
Derivatives in cash flow hedging relationships
Impact of derivative instruments and their location within Condensed Consolidated Statement of Operations
Amount of Gain (Loss) Recognized in AOCI on Derivative (Effective Portion)	(179)
Interest Expense. \| Derivatives in cash flow hedging relationships
Impact of derivative instruments and their location within Condensed Consolidated Statement of Operations
Amount of Gain (Loss) Reclassified from AOCI into income (Effective Portion)	$ (1,407)

Represents the number of vessels mortgaged by the entity as collateral in support of agreements.

No definition available.

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

+ Details

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Balance Type:	debit
Period Type:	instant

- Details

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624177-113959

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

+ Details

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