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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation expected to be expensed in the second fiscal year following the latest fiscal year.

No definition available.

Name:	gnk_EmployeeServiceShareBasedCompensationNonvestedAwardsCompensationNotYetRecognizedShareBasedAwardsOtherThanOptionsYearTwo
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This element represents the fair value of each warrant upon emergence from bankruptcy.

No definition available.

Name:	gnk_FairValueOfWarrant
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Represents the number of members who resigned from the Company's Board of Directors.

No definition available.

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Represents the number of tiers of Management Incentive Plan ("MIP") Warrants.

No definition available.

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Represents the percentage of Shares of post emergence common stock outstanding as of the Effective Date on a fully-diluted basis under 2014 Management Incentive Plan

No definition available.

Name:	gnk_PercentageOfSharesInPostEmergenceCommonStockOutstanding
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Represents the number of common stock currently outstanding in respect of RSUs.

No definition available.

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The number of shares into which fully or partially vested equity instruments, excluding stock (or unit) options, outstanding as of the balance sheet date can be currently converted under the option plan.

No definition available.

Name:	gnk_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisableNumber
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The weighted average exercise price at grant date for nonvested equity-based awards exercisable during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

No definition available.

Name:	gnk_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExercisableNumberWeightedAverageGrantDateExercisePrice
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Weighted average remaining contractual term for exercisable equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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The weighted average exercise price at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

No definition available.

Name:	gnk_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateExercisePrice
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The weighted average exercise price of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

No definition available.

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Fair value of share-based awards outstanding other than options.

No definition available.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period, on a post reverse stock split basis.

No definition available.

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The weighted average exercise price of exercisable warrants.

No definition available.

Name:	gnk_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageExercisePriceExercisableWarrants
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"The maximum number of shares after reverse stock split (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). "

No definition available.

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Number of other than options vested.

No definition available.

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Represents the number of anniversaries in which award vests.

No definition available.

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Represents the number of warrants exercisable as of the report date.

No definition available.

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Exercise price per share or per unit of warrants or rights outstanding.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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No definition available.

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No definition available.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

No definition available.

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Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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No definition available.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:sharesItemType
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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The risk-free interest rate assumption that is used in valuing an option on its own shares.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Percentage of vesting of share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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No definition available.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reduction in the number of shares during the period as a result of a reverse stock split.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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