Name:	gnk_ScheduleOfInterestRatesTableTextBlock
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Tabular disclosure of long-term debt less short-term debt arrangements (having initial terms of repayment within one year or the normal operating cycle, if longer) as of the balance sheet date.

No definition available.

Name:	gnk_ScheduleOfLongTermDebtAndCurrentPortionOfLongTermDebtTableTextBlock
Namespace Prefix:	gnk_
Data Type:	nonnum:textBlockItemType
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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.

No definition available.

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

Tabular disclosure of information pertaining to short-term and long-debt instruments or arrangements, including but not limited to identification of terms, features, collateral requirements and other information necessary to a fair presentation.

No definition available.

Name:	us-gaap_ScheduleOfDebtTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

Tabular disclosure of the combined aggregate amount of maturities and sinking fund requirements for all long-term borrowings for each of the five years following the date of the latest balance sheet date presented.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601