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Summary of Significant Accounting Policies Property, Plant and Equipment (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | $ 10,098.9 us-gaap_PropertyPlantAndEquipmentGross |  | $ 9,651.6 us-gaap_PropertyPlantAndEquipmentGross |  |
Accumulated Depreciation | 3,119.0 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment |  | 2,978.8 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment |  |
Net property, plant and equipment | 6,979.9 us-gaap_PropertyPlantAndEquipmentNet |  | 6,672.8 us-gaap_PropertyPlantAndEquipmentNet |  |
Capitalized Computer Software, Gross | 38.1 us-gaap_CapitalizedComputerSoftwareNet |  | 24.0 us-gaap_CapitalizedComputerSoftwareNet |  |
Capitalized Computer Software, Amortization | 9.5 us-gaap_CapitalizedComputerSoftwareAmortization |  | 11.2 us-gaap_CapitalizedComputerSoftwareAmortization |  | 14.1 us-gaap_CapitalizedComputerSoftwareAmortization
McClain Plant [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Jointly Owned Utility Plant, Proportionate Ownership Share | 77.00%us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember | [1] | 77.00%us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember | [2] |
Property, Plant and Equipment, Gross | 207.7 us-gaap_PropertyPlantAndEquipmentGross / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember | [1] | 183.2 us-gaap_PropertyPlantAndEquipmentGross / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember | [2] |
Accumulated Depreciation | 46.6 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember | [1] | 62.8 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember | [2] |
Net property, plant and equipment | 161.1 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember | [1] | 120.4 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember | [2] |
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress | 0.5 us-gaap_JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember |  | 0.1 us-gaap_JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress / us-gaap_JointlyOwnedUtilityPlantAxis = oge_McclainPlantMember |  |
Redbud Plant [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Jointly Owned Utility Plant, Proportionate Ownership Share | 51.00%us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember | [1],[3] | 51.00%us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember | [2],[4] |
Property, Plant and Equipment, Gross | 484.1 us-gaap_PropertyPlantAndEquipmentGross / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember | [1],[3] | 498.9 us-gaap_PropertyPlantAndEquipmentGross / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember | [2],[4] |
Accumulated Depreciation | 81.8 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember | [1],[3] | 89.7 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember | [2],[4] |
Net property, plant and equipment | 402.3 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember | [1],[3] | 409.2 us-gaap_PropertyPlantAndEquipmentNet / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember | [2],[4] |
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress | 0.4 us-gaap_JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember |  | 39.5 us-gaap_JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember |  |
Amount of Acquisition Adjustments | 148.3 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1 / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember |  | 148.3 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1 / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember |  |
Public Utilities, Property, Plant and Equipment, Amount of Acquisition Adjustments, Related Accumulated Depreciation | 34.3 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustmentsRelatedAccumulatedDepreciation1 / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember |  | 28.8 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustmentsRelatedAccumulatedDepreciation1 / us-gaap_JointlyOwnedUtilityPlantAxis = oge_RedbudPlantMember |  |
OGE Energy [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | 151.7 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgeEnergyMember |  | 152.4 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgeEnergyMember |  |
Accumulated Depreciation | 113.3 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgeEnergyMember |  | 114.2 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgeEnergyMember |  |
Net property, plant and equipment | 38.4 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgeEnergyMember |  | 38.2 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgeEnergyMember |  |
Capitalized Computer Software, Gross | 4.5 us-gaap_CapitalizedComputerSoftwareNet / dei_LegalEntityAxis = oge_OgeEnergyMember |  | 7.2 us-gaap_CapitalizedComputerSoftwareNet / dei_LegalEntityAxis = oge_OgeEnergyMember |  |
Capitalized Computer Software, Amortization | 4.3 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_OgeEnergyMember |  | 6.4 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_OgeEnergyMember |  | 6.8 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_OgeEnergyMember
OGE Energy [Member] | Total Property Plant and Equipment [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | 151.7 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgeEnergyMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  | 152.4 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgeEnergyMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  |
Accumulated Depreciation | 113.3 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgeEnergyMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  | 114.2 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgeEnergyMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  |
Net property, plant and equipment | 38.4 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgeEnergyMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  | 38.2 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgeEnergyMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  |
Og and E [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Capitalized Computer Software, Gross | 33.6 us-gaap_CapitalizedComputerSoftwareNet / dei_LegalEntityAxis = oge_OgAndEMember |  | 16.8 us-gaap_CapitalizedComputerSoftwareNet / dei_LegalEntityAxis = oge_OgAndEMember |  |
Capitalized Computer Software, Amortization | 5.2 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_OgAndEMember |  | 4.0 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_OgAndEMember |  | 4.2 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_OgAndEMember
Og and E [Member] | Total Property Plant and Equipment [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | 9,947.2 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  | 9,499.2 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  |
Accumulated Depreciation | 3,005.7 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  | 2,864.6 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  |
Net property, plant and equipment | 6,941.5 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  | 6,634.6 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_TotalPropertyPlantAndEquipmentMember |  |
Og and E [Member] | Electric Transmission and Distribution [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | 3,559.5 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionAndDistributionMember |  | 3,403.8 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionAndDistributionMember |  |
Accumulated Depreciation | 1,086.7 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionAndDistributionMember |  | 1,028.2 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionAndDistributionMember |  |
Net property, plant and equipment | 2,472.8 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionAndDistributionMember |  | 2,375.6 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionAndDistributionMember |  |
Og and E [Member] | Electric Generation Equipment [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | 3,620.1 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember | [5] | 3,551.0 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember | [6] |
Accumulated Depreciation | 1,345.1 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember | [5] | 1,306.1 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember | [6] |
Net property, plant and equipment | 2,275.0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember | [5] | 2,244.9 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember | [6] |
Amount of Acquisition Adjustments | 148.3 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1 / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember |  | 148.3 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1 / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember |  |
Public Utilities, Property, Plant and Equipment, Amount of Acquisition Adjustments, Related Accumulated Depreciation | 34.3 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustmentsRelatedAccumulatedDepreciation1 / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember |  | 28.8 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustmentsRelatedAccumulatedDepreciation1 / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricGenerationEquipmentMember |  |
Og and E [Member] | Electric Transmission [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | 2,370.0 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember | [7] | 2,163.7 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember | [8] |
Accumulated Depreciation | 417.8 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember | [7] | 385.0 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember | [8] |
Net property, plant and equipment | 1,952.2 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember | [7] | 1,778.7 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember | [8] |
Amount of Acquisition Adjustments | 3.3 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1 / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember |  | 3.3 us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAmountOfAcquisitionAdjustments1 / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember |  |
Amount of Acquistion Adjustments Related Accumulated Amortization | 0.4 oge_AmountOfAcquistionAdjustmentsRelatedAccumulatedAmortization / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember |  | 0.3 oge_AmountOfAcquistionAdjustmentsRelatedAccumulatedAmortization / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_ElectricTransmissionMember |  |
Og and E [Member] | Finite-Lived Intangible Assets, Major Class Name [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | 67.6 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_FiniteLivedIntangibleAssetsMajorClassNameMember |  | 50.5 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_FiniteLivedIntangibleAssetsMajorClassNameMember |  |
Accumulated Depreciation | 31.1 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_FiniteLivedIntangibleAssetsMajorClassNameMember |  | 27.1 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_FiniteLivedIntangibleAssetsMajorClassNameMember |  |
Net property, plant and equipment | 36.5 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_FiniteLivedIntangibleAssetsMajorClassNameMember |  | 23.4 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = oge_FiniteLivedIntangibleAssetsMajorClassNameMember |  |
Og and E [Member] | Property, Plant and Equipment, Other Types [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Property, Plant and Equipment, Gross | 330.0 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_PropertyPlantAndEquipmentOtherTypesMember |  | 330.2 us-gaap_PropertyPlantAndEquipmentGross / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_PropertyPlantAndEquipmentOtherTypesMember |  |
Accumulated Depreciation | 125.0 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_PropertyPlantAndEquipmentOtherTypesMember |  | 118.2 us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_PropertyPlantAndEquipmentOtherTypesMember |  |
Net property, plant and equipment | 205.0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_PropertyPlantAndEquipmentOtherTypesMember |  | 212.0 us-gaap_PropertyPlantAndEquipmentNet / dei_LegalEntityAxis = oge_OgAndEMember / us-gaap_PropertyPlantAndEquipmentByTypeAxis = us-gaap_PropertyPlantAndEquipmentOtherTypesMember |  |
Enogex [Member] |  |  |  |  |
Property, Plant and Equipment [Line Items] |  |  |  |  |
Capitalized Computer Software, Amortization | $ 0 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_EnogexMember |  | $ 0.8 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_EnogexMember |  | $ 3.1 us-gaap_CapitalizedComputerSoftwareAmortization / dei_LegalEntityAxis = oge_EnogexMember
[1] | Construction work in progress was $0.5 million and $0.4 million for the McClain and Redbud Plants, respectively.
[2] | Construction work in progress was $0.1 million and $39.5 million for the McClain and Redbud Plants, respectively.
[3] | This amount includes a plant acquisition adjustment of $148.3 million and accumulated amortization of $34.3 million.
[4] | This amount includes a plant acquisition adjustment of $148.3 million and accumulated amortization of $28.8 million.
[5] | This amount includes a plant acquisition adjustment of $148.3 million and accumulated amortization of $34.3 million.
[6] | This amount includes a plant acquisition adjustment of $148.3 million and accumulated amortization of $28.8 million.
[7] | This amount includes a plant acquisition adjustment of $3.3 million and accumulated amortization of $0.4 million.
[8] | This amount includes a plant acquisition adjustment of $3.3 million and accumulated amortization of $0.3 million.

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- Definition The proportionate share of interest (percent) in a jointly owned utility plant. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 10.C) -URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 10 -Section C + Details
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- Definition Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph a -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 8 -Article 7 + Details
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- Definition Amount of acquisition adjustments included in property, plant and equipment (PPE) for utilities. + References No definition available. + Details
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