XML 68 R57.htm IDEA: XBRL DOCUMENT
v3.22.2.2

FAIR VALUE MEASUREMENTS - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 4 Months Ended | 9 Months Ended
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2021 | Sep. 30, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Contingent consideration arrangement | $ 4.9 |  |  | $ 4.9
Contingent consideration, loss to change in value | 0.3 | $ 1.2 | $ 0.1 | 0.4
Prepaid Expenses and Other Current Assets |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Contingent consideration arrangement | 0.6 |  |  | 0.6
Other Noncurrent Assets |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Contingent consideration arrangement | $ 4.3 |  |  | $ 4.3

X
- Definition Contingent Consideration, Asset, Fair Value + References No definition available. + Details
Name: | gpor_ContingentConsiderationAssetFairValue
Namespace Prefix: | gpor_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Contingent Consideration, Change In Amount, Asset + References No definition available. + Details
Name: | gpor_ContingentConsiderationChangeInAmountAsset
Namespace Prefix: | gpor_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=us-gaap_OtherNoncurrentAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |