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v3.19.3.a.u2

Subsequent Events (Details) MMBTU in Thousands, $ in Millions |  | 2 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 02, 2020 USD ($) | Feb. 27, 2020 MMBTU $ / MMBTU | Jan. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Subsequent Event [Line Items] |  |  |  |
Repurchased face amount |  |  |  | $ 200.0
Subsequent Event |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Proceeds from sale of assets | $ 50.0 |  |  |
Incentive payments, term | 15 years |  |  |
Senior notes | Subsequent Event |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Repurchased face amount |  |  | $ 10.2 |
Debt instrument, repurchase amount |  |  | $ 6.9 |
Early Termination, Fixed Price Swaps | Subsequent Event |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Daily Volume (MMBtu/day) | MMBTU |  | 294 |  |
Fixed Price Swap 2020 April, May | Subsequent Event |  |  |  |
Subsequent Event [Line Items] |  |  |  |
Daily Volume (MMBtu/day) | MMBTU |  | 472 |  |
Early terminations, weighted average price | $ / MMBTU |  | 2.85 |  |

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- Definition Sale Of Assets, Incentive Payments, Term + References No definition available. + Details
Name: | gpor_SaleOfAssetsIncentivePaymentsTerm
Namespace Prefix: | gpor_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Fair value amount of debt instrument that was repurchased. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Face (par) amount of the original debt instrument that was repurchased. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition Nominal energy measure used to calculate payments on a derivative instrument. + References No definition available. + 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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- Definition The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585 + Details
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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- Details
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- Details
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- Details
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Namespace Prefix: |
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- Details
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