XML 109 R91.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Supplemental Information on Oil and Gas Exploration and Production Activities (Unaudited) - Costs Incurred In Oil and Gas Property Acquisition and Development Activities (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items] |  |  |
Acquisition | $ 152,887 | $ 810,755 | $ 440,288
Development of proved undeveloped properties | 423,998 | 642,811 | 864,511
Exploratory | 0 | 0 | 2,249
Recompletions | 16,386 | 13,894 | 45,658
Capitalized asset retirement obligation | 10,971 | 8,800 | 2,095
Total | 604,242 | 1,476,260 | 1,354,801
Investment in Grizzly Oil Sands ULC |  |  |
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items] |  |  |
Acquisition | 357 | 396 | 1,230
Development of proved undeveloped properties | 0 | 47 | 7,107
Exploratory | 0 | 0 | 0
Capitalized asset retirement obligation | 784 | 282 | 1,055
Total | $ 1,141 | $ 725 | $ 9,392

X
- Definition Costs incurred for the recompletion of oil and gas wells + References No definition available. + Details
Name: | gpor_CostsIncurredRecompletionsOfOilAndGasProperties
Namespace Prefix: | gpor_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Total costs incurred in oil and gas properties acquisition and development activities + References No definition available. + Details
Name: | gpor_TotalCostsIncurredInOilAndGasPropertiesAcquisitionAndDevelopmentActivities
Namespace Prefix: | gpor_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Cost incurred, including capitalized costs and costs charged to expense, in acquisition of oil and gas properties. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 18 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62014-109447 + Details
Name: | us-gaap_CostsIncurredAcquisitionOfOilAndGasProperties
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of asset retirement obligations (ARO) costs incurred (whether capitalized or charged to expense) during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
Name: | us-gaap_CostsIncurredAssetRetirementObligationIncurred
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Development costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 18 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62014-109447 + Details
Name: | us-gaap_CostsIncurredDevelopmentCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Exploration costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Exploration -URI http://asc.fasb.org/extlink&oid=6512329 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 18 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62014-109447 + Details
Name: | us-gaap_CostsIncurredExplorationCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_CostsIncurredOilAndGasPropertyAcquisitionExplorationAndDevelopmentActivitiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=gpor_GrizzlyOilSandsUlcMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |