Supplemental Information On Oil And Gas Exploration And Production Activities (Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves) (Details) (USD $)
In Thousands, unless otherwise specified |
12 Months Ended | ||
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] | |||
Future cash flows | $ 4,667,678us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows | $ 1,657,708us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows | $ 954,833us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows |
Future development and abandonment costs | (719,898)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 | (272,500)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 | (159,113)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 |
Future production costs | (880,427)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 | (274,428)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 | (147,024)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 |
Future production taxes | (71,229)gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes | (78,647)gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes | (89,175)gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes |
Future income taxes | (693,154)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 | (172,691)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 | (114,867)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 |
Future net cash flows | 2,302,970us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows | 859,442us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows | 444,654us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows |
10% discount to reflect timing of cash flows | (875,803)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows | (280,976)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows | (96,013)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows |
Standardized measure of discounted future net cash flows | 1,427,167us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure | 578,466us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure | 348,641us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure |
Diamondback Energy, Inc [Member] | |||
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] | |||
Future cash flows |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
331,505us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
592,669us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
Future development and abandonment costs |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(37,229)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(115,869)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
Future production costs |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(58,096)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(165,553)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
Future production taxes |
0gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(22,925)gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(30,122)gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
Future income taxes |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(48,547)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(71,669)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
Future net cash flows |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
164,708us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
209,456us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
10% discount to reflect timing of cash flows |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(94,462)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
(130,871)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
Standardized measure of discounted future net cash flows |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
70,246us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
78,585us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_DiamondbackEnergyIncMember |
Grizzly Oil Sands ULC [Member] | |||
Discounted Future Net Cash Flows Relating to Proved Oil and Gas Reserves [Line Items] | |||
Future cash flows |
754,720us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
Future development and abandonment costs |
(205,242)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
Future production costs |
(291,988)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
Future production taxes |
0gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0gpor_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionTaxes / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
Future income taxes |
(11,250)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1 / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
Future net cash flows |
246,240us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
10% discount to reflect timing of cash flows |
(152,494)us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
Standardized measure of discounted future net cash flows |
$ 93,746us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
$ 0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
$ 0us-gaap_DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure / us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis = gpor_GrizzlyOilSandsUlcMember |
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- Definition
Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Production Taxes No definition available.
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- Definition
This is the amount that is derived from using a discount rate of ten percent a year to reflect the timing of the future net cash flows relating to proved oil and gas reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of estimated future cash inflows from sale of proved oil and gas reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of estimated future cost to be incurred in developing proved oil and gas reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of estimated future income tax expense to be incurred based on the future income less future expense derived from production and sale of proved oil and gas reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of estimated net future cash inflows, after subtracting future development and production costs and future income tax expenses, from sale of proved oil and gas reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Amount of estimated future cost to be incurred in producing proved oil and gas reserves. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
This amount is the future net cash flows less the computed discount. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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