XML 50 R40.htm IDEA: XBRL DOCUMENT
v3.23.3

BASIS OF PRESENTATION - Narrative (Details) - USD ($) $ in Millions |  |  | 9 Months Ended
--- | --- | --- | ---
Feb. 24, 2023 | Feb. 21, 2023 | Sep. 30, 2023 | Sep. 30, 2022
Accounting Policies [Abstract] |  |  |  |
Noninterest income |  |  | $ 17.8 | $ 11.5
Litigation settlement, expense |  | $ 1.0 | 1.0 | 5.1
Proceeds from plan of reorganization, recoupment of collateral |  |  | $ 5.0 |
Litigation settlement, amount awarded from other party | $ 17.8 |  |  | $ 5.2

X
- Definition Proceeds From Plan Of Reorganization, Recoupment Of Collateral + References No definition available. + Details
Name: | gpor_ProceedsFromPlanOfReorganizationRecoupmentOfCollateral
Namespace Prefix: | gpor_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Definition Amount awarded from other party in judgment or settlement of litigation. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementAmountAwardedFromOtherParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of revenue earned, classified as other, excluding interest income. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-03(1)(e)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1 + Details
Name: | us-gaap_NoninterestIncomeOtherOperatingIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration