XML 45 R75.htm IDEA: XBRL DOCUMENT
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Hedging Activities (Schedule Of Derivative Instruments) (Details) | Dec. 31, 2014
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Fixed Price Swap, January 2014 [Member] |
Derivative [Line Items] |
Daily Volume | 190,625 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuary2014Member
Weighted Average Price | 4.12 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuary2014Member
Fixed Price Swap, February Though December 2014 [Member] |
Derivative [Line Items] |
Daily Volume | 191,250 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapFebruaryThoughDecember2014Member
Weighted Average Price | 4.05 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapFebruaryThoughDecember2014Member
Fixed Price Swap, May 2015 through June 2015 [Member] |
Derivative [Line Items] |
Daily Volume | 201,250 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapMay2015throughJune2015Member
Weighted Average Price | 4.05 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapMay2015throughJune2015Member
Fixed Price Swap, July 2015 through September 2015 [Member] |
Derivative [Line Items] |
Daily Volume | 216,875 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJuly2015throughSeptember2015Member
Weighted Average Price | 4.04 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJuly2015throughSeptember2015Member
Fixed Price Swap, January through December 2015 [Member] |
Derivative [Line Items] |
Daily Volume | 232,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuarythroughDecember2015Member
Weighted Average Price | 4.04 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuarythroughDecember2015Member
Fixed Price Swap, Period of January through March 2016 [Member] |
Derivative [Line Items] |
Daily Volume | 172,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapPeriodofJanuarythroughMarch2016Member
Weighted Average Price | 3.99 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapPeriodofJanuarythroughMarch2016Member
Fixed Price Swap, April 2016 [Member] |
Derivative [Line Items] |
Daily Volume | 162,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2016Member
Weighted Average Price | 3.99 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2016Member
Fixed Price Swap, May 2016 through December 2016 [Member] |
Derivative [Line Items] |
Daily Volume | 92,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapMay2016throughDecember2016Member
Weighted Average Price | 3.97 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapMay2016throughDecember2016Member
Fixed Price Swap, January 2017 through June 2017 [Member] |
Derivative [Line Items] |
Daily Volume | 62,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuary2017throughJune2017Member
Weighted Average Price | 3.96 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuary2017throughJune2017Member

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- Definition Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Average fixed price related to the group of price risk swap derivatives. + References No definition available. + Details
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