XML 17 R55.htm IDEA: XBRL DOCUMENT
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Hedging Activities (Schedule Of Derivative Instruments) (Details) | Mar. 31, 2015
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Fixed Price Swap, April 2015 through June 2016 [Member] |
Derivative [Line Items] |
Daily Volume | 1,000 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2015throughJune2016Member
Weighted Average Price | 62.25 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2015throughJune2016Member
Fixed Price Swap, April 2015 [Member] |
Derivative [Line Items] |
Daily Volume | 191,250 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FuelPriceSwapApril2015Member
Weighted Average Price | 4.05 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FuelPriceSwapApril2015Member
Fixed Price Swap, May through June 2015 [Member] |
Derivative [Line Items] |
Daily Volume | 201,250 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapMaythroughJune2015Member
Weighted Average Price | 4.05 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapMaythroughJune2015Member
Fixed Price Swap, July through August 2015 [Member] |
Derivative [Line Items] |
Daily Volume | 216,875 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJulythroughAugust2015Member
Weighted Average Price | 4.04 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJulythroughAugust2015Member
Fixed Price Swap, September 2015 [Member] |
Derivative [Line Items] |
Daily Volume | 246,875 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapSeptember2015Member
Weighted Average Price | 3.97 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapSeptember2015Member
Fixed Price Swap, October through December 2015 [Member] |
Derivative [Line Items] |
Daily Volume | 262,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapOctoberthroughDecember2015Member
Weighted Average Price | 3.96 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapOctoberthroughDecember2015Member
Fixed Price Swap, January through March 2016 [Member] |
Derivative [Line Items] |
Daily Volume | 252,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuarythroughMarch2016Member
Weighted Average Price | 3.82 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuarythroughMarch2016Member
Fixed Price Swap, April 2016 [Member] |
Derivative [Line Items] |
Daily Volume | 242,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2016Member
Weighted Average Price | 3.81 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2016Member
Fixed Price Swap, May through December 2016 [Member] |
Derivative [Line Items] |
Daily Volume | 172,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FuelPriceSwapMaythroughDecember2016Member
Weighted Average Price | 3.73 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FuelPriceSwapMaythroughDecember2016Member
Fixed Price Swap, January through June 2017 [Member] |
Derivative [Line Items] |
Daily Volume | 142,500 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuarythroughJune2017Member
Weighted Average Price | 3.67 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuarythroughJune2017Member
Fixed Price Swap, July through December 2017 [Member] |
Derivative [Line Items] |
Daily Volume | 80,000 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJulythroughDecember2017Member
Weighted Average Price | 3.45 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJulythroughDecember2017Member
Fixed Price Swap, January through December 2018 [Member] |
Derivative [Line Items] |
Daily Volume | 30,000 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuarythroughDecember2018Member
Weighted Average Price | 3.40 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapJanuarythroughDecember2018Member
Fixed Price Swap, April 2015 through December 2016, Option One [Member] |
Derivative [Line Items] |
Daily Volume | 30,000 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2015throughDecember2016OptionOneMember
Weighted Average Price | 0.02 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2015throughDecember2016OptionOneMember
Fixed Price Swap, April 2015 through December 2016, Option Two [Member] |
Derivative [Line Items] |
Daily Volume | 10,000 invest_DerivativeNonmonetaryNotionalAmount / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2015throughDecember2016OptionTwoMember
Weighted Average Price | 0.01 us-gaap_DerivativeSwapTypeAverageFixedPrice / us-gaap_DerivativeByNatureAxis = gpor_FixedPriceSwapApril2015throughDecember2016OptionTwoMember

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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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