XML 98 R69.htm IDEA: XBRL DOCUMENT v2.4.1.9
Retirement Plans and Postretirement Benefit Plans (Details) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Employer contributions $ 0us-gaap_DefinedBenefitPlanContributionsByEmployer $ 35.0us-gaap_DefinedBenefitPlanContributionsByEmployer  
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Employer contributions 0us-gaap_DefinedBenefitPlanContributionsByEmployer 35.0us-gaap_DefinedBenefitPlanContributionsByEmployer  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Net periodic benefit cost 19.3us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost 60.0us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost 51.4us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
Effect of One Percentage Point Increase on Service and Interest Cost Components 0us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents 0us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents 0us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents
Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation 0.1us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation 0.1us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation 0.1us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation
Effect of One Percentage Point Decrease on Service and Interest Cost Components 0.1us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1 0.1us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1 0.1us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1
Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation 0.7us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1 0.6us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1 0.9us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1
Expected Future Benefit Payments, Next Twelve Months 98.3us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths    
Expected Future Benefit Payments, Year Two 80.6us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo    
Expected Future Benefit Payments, Year Three 75.6us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree    
Expected Future Benefit Payments, Year Four 70.4us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour    
Expected Future Benefit Payments, Year Five 84.8us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive    
Expected Future Benefit Payments, Five Fiscal Years Thereafter 247.8us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter    
Defined Contribution Plan, Cost Recognized 15.2us-gaap_DefinedContributionPlanCostRecognized 14.2us-gaap_DefinedContributionPlanCostRecognized 13.4us-gaap_DefinedContributionPlanCostRecognized
Other Postretirement Benefit Plans, Defined Benefit [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Employer contributions 7.1us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
8.8us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Pension settlement charges 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]      
Benefit Obligation, Beginning 258.2us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
301.0us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Service cost 3.1us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.3us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.1us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Actual return on plans' assets 11.4us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
10.3us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
11.9us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Plan curtailments (0.6)us-gaap_DefinedBenefitPlanCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Plan settlements 0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Participants' contributions 3.4us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
3.4us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Actuarial gains (losses) 19.5us-gaap_DefinedBenefitPlanActuarialGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(46.7)us-gaap_DefinedBenefitPlanActuarialGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Benefits paid (14.1)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(14.1)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Benefit Obligation, Ending 280.9us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
258.2us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
301.0us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Beginning 61.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
59.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Actual return on plans' assets 1.8us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
3.7us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Employer contributions 7.1us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
8.8us-gaap_DefinedBenefitPlanContributionsByEmployer
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Plan settlements 0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Participants' contributions 3.4us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
3.4us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Benefits paid (14.1)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(14.1)us-gaap_DefinedBenefitPlanBenefitsPaid
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Fair Value of Plan Assets, Ending 59.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
61.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
59.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Funded Status of Plan (221.3)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(196.8)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
 
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Service cost 3.1us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.3us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.1us-gaap_DefinedBenefitPlanServiceCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Interest cost 11.4us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
10.3us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
11.9us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Expected return on plan assets (2.4)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(2.5)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(3.0)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Amortization of transition obligations 0us-gaap_DefinedBenefitPlanAmortizationOfTransitionObligationsAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanAmortizationOfTransitionObligationsAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
2.7us-gaap_DefinedBenefitPlanAmortizationOfTransitionObligationsAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Amortization of net loss 12.3us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
21.5us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
20.6us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Amortization of unrecognized prior service cost (16.5)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(16.5)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
(16.5)us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Curtailment 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Settlement 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Net periodic benefit cost 7.9us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
17.1us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
19.8us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Amount Attributable to Unconsolidated Affiliates 1.3oge_AmountAttributabletoUnconsolidatedAffiliates
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
1.5oge_AmountAttributabletoUnconsolidatedAffiliates
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
0oge_AmountAttributabletoUnconsolidatedAffiliates
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Net Periodic Benefit Cost, Net of Unconsolidated Affiliates 6.6oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
15.6oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
19.8oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Capitalized Portion of Net Periodic Benefit Cost 2.0oge_CapitalizedPortionOfNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.5oge_CapitalizedPortionOfNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
5.6oge_CapitalizedPortionOfNetPeriodicBenefitCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Assumptions Used Calculating Benefit Obligation, Discount Rate 3.80%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
3.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets 4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Health Care Cost Trend Rate Assumed for Next Fiscal Year 7.85%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
8.35%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
8.55%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Ultimate Health Care Cost Trend Rate 4.48%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.48%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
4.48%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Year that Rate Reaches Ultimate Trend Rate 2028 2028 2028
Fair Value of Plan Assets 59.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
61.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
59.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Other Postretirement Benefit Plans, Defined Benefit [Member] | OKLAHOMA      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Additional Postretirement Medical Expense to Meet State Requirements 5.2oge_AdditionalPostretirementMedicalExpenseToMeetStateRequirements
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0.6oge_AdditionalPostretirementMedicalExpenseToMeetStateRequirements
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0.8oge_AdditionalPostretirementMedicalExpenseToMeetStateRequirements
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Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 8.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 8.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 51.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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53.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 51.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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53.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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Restoration of Retirement Income Plan [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
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0.2us-gaap_DefinedBenefitPlanContributionsByEmployer
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Pension settlement charges 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]      
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1.0us-gaap_DefinedBenefitPlanServiceCost
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0.6us-gaap_DefinedBenefitPlanInterestCost
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Plan curtailments 0us-gaap_DefinedBenefitPlanCurtailments
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Plan settlements 0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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Participants' contributions 0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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Actuarial gains (losses) 4.1us-gaap_DefinedBenefitPlanActuarialGainLoss
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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Benefits paid (0.1)us-gaap_DefinedBenefitPlanBenefitsPaid
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Benefit Obligation, Ending 19.7us-gaap_DefinedBenefitPlanBenefitObligation
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14.0us-gaap_DefinedBenefitPlanBenefitObligation
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Beginning 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Actual return on plans' assets 0us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets
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Employer contributions 0.1us-gaap_DefinedBenefitPlanContributionsByEmployer
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0.2us-gaap_DefinedBenefitPlanContributionsByEmployer
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Plan settlements 0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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Participants' contributions 0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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Benefits paid (0.1)us-gaap_DefinedBenefitPlanBenefitsPaid
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Fair Value of Plan Assets, Ending 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Funded Status of Plan (19.7)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Service cost 1.1us-gaap_DefinedBenefitPlanServiceCost
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1.0us-gaap_DefinedBenefitPlanServiceCost
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Interest cost 0.6us-gaap_DefinedBenefitPlanInterestCost
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0.6us-gaap_DefinedBenefitPlanInterestCost
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Expected return on plan assets 0us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
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0us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
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Amortization of transition obligations 0us-gaap_DefinedBenefitPlanAmortizationOfTransitionObligationsAssets
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0us-gaap_DefinedBenefitPlanAmortizationOfTransitionObligationsAssets
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0us-gaap_DefinedBenefitPlanAmortizationOfTransitionObligationsAssets
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Amortization of net loss 0.2us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss
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0.4us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss
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0.4us-gaap_DefinedBenefitPlanFutureAmortizationOfGainLoss
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Amortization of unrecognized prior service cost 0.2us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
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0.3us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
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0.7us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
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Curtailment 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
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0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
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0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
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Settlement 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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0.9us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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Net periodic benefit cost 2.1us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
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2.4us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
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3.6us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
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Amount Attributable to Unconsolidated Affiliates 0.1oge_AmountAttributabletoUnconsolidatedAffiliates
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0.1oge_AmountAttributabletoUnconsolidatedAffiliates
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0oge_AmountAttributabletoUnconsolidatedAffiliates
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Net Periodic Benefit Cost, Net of Unconsolidated Affiliates 2.0oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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2.3oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
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3.6oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
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Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Plans, Defined Benefit [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Employer contributions 0us-gaap_DefinedBenefitPlanContributionsByEmployer
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35.0us-gaap_DefinedBenefitPlanContributionsByEmployer
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Pension settlement charges 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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22.4us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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Accumulated Benefit Obligation 688.4us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation
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623.4us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation
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Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]      
Benefit Obligation, Beginning 658.1us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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747.1us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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Service cost 15.3us-gaap_DefinedBenefitPlanServiceCost
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19.0us-gaap_DefinedBenefitPlanServiceCost
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17.9us-gaap_DefinedBenefitPlanServiceCost
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Actual return on plans' assets 28.1us-gaap_DefinedBenefitPlanInterestCost
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26.7us-gaap_DefinedBenefitPlanInterestCost
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30.1us-gaap_DefinedBenefitPlanInterestCost
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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Plan curtailments (0.7)us-gaap_DefinedBenefitPlanCurtailments
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0us-gaap_DefinedBenefitPlanCurtailments
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Plan settlements 0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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(67.5)us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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Participants' contributions 0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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Actuarial gains (losses) 79.3us-gaap_DefinedBenefitPlanActuarialGainLoss
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Benefits paid (55.1)us-gaap_DefinedBenefitPlanBenefitsPaid
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Benefit Obligation, Ending 725.0us-gaap_DefinedBenefitPlanBenefitObligation
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Beginning 654.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Employer contributions 0us-gaap_DefinedBenefitPlanContributionsByEmployer
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35.0us-gaap_DefinedBenefitPlanContributionsByEmployer
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Plan settlements 0us-gaap_DefinedBenefitPlanSettlementsBenefitObligation
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Participants' contributions 0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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0us-gaap_DefinedBenefitPlanContributionsByPlanParticipants
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Benefits paid (55.1)us-gaap_DefinedBenefitPlanBenefitsPaid
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Fair Value of Plan Assets, Ending 679.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Funded Status of Plan (45.2)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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19.0us-gaap_DefinedBenefitPlanServiceCost
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17.9us-gaap_DefinedBenefitPlanServiceCost
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26.7us-gaap_DefinedBenefitPlanInterestCost
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30.1us-gaap_DefinedBenefitPlanInterestCost
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Expected return on plan assets (45.3)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
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Curtailment (0.2)us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
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0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments
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Settlement 0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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22.4us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
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48.0us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
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28.0us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
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Amount Attributable to Unconsolidated Affiliates 3.2oge_AmountAttributabletoUnconsolidatedAffiliates
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5.9oge_AmountAttributabletoUnconsolidatedAffiliates
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0oge_AmountAttributabletoUnconsolidatedAffiliates
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Net Periodic Benefit Cost, Net of Unconsolidated Affiliates 10.7oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
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42.1oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
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28.0oge_DefinedBenefitPlanNetPeriodicBenefitCostNetOfUnconsolidatedAffiliates
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Capitalized Portion of Net Periodic Benefit Cost 3.4oge_CapitalizedPortionOfNetPeriodicBenefitCost
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6.4oge_CapitalizedPortionOfNetPeriodicBenefitCost
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7.5oge_CapitalizedPortionOfNetPeriodicBenefitCost
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Assumptions Used Calculating Benefit Obligation, Discount Rate 3.80%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
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4.60%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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3.70%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets 7.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
8.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
8.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase 4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
4.20%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
Fair Value of Plan Assets 679.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_PensionPlansDefinedBenefitMember
654.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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626.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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Pension Plans, Defined Benefit [Member] | OKLAHOMA      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Pension settlement charges   17.0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ dei_EntityByLocationAxis
= stpr_OK
 
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Settlement   17.0us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ dei_EntityByLocationAxis
= stpr_OK
 
Additional Pension Expense to Meet State Requirements 11.2oge_AdditionalPensionExpenseToMeetStateRequirements
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ dei_EntityByLocationAxis
= stpr_OK
5.8oge_AdditionalPensionExpenseToMeetStateRequirements
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ dei_EntityByLocationAxis
= stpr_OK
8.3oge_AdditionalPensionExpenseToMeetStateRequirements
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ dei_EntityByLocationAxis
= stpr_OK
Pension Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 3 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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Pension Plans, Defined Benefit [Member] | U.S. common stocks [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 201.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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/ invest_InvestmentSecuritiesSeriesAxis
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236.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_PensionPlansDefinedBenefitMember
/ invest_InvestmentSecuritiesSeriesAxis
= oge_USCommonStocksMember
 
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 201.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ invest_InvestmentSecuritiesSeriesAxis
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236.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_PensionPlansDefinedBenefitMember
/ invest_InvestmentSecuritiesSeriesAxis
= oge_USCommonStocksMember
 
Pension Plans, Defined Benefit [Member] | U.S. common stocks [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 201.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
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236.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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= us-gaap_FairValueInputsLevel1Member
/ invest_InvestmentSecuritiesSeriesAxis
= oge_USCommonStocksMember
 
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 201.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ invest_InvestmentSecuritiesSeriesAxis
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236.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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/ us-gaap_FairValueByFairValueHierarchyLevelAxis
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/ invest_InvestmentSecuritiesSeriesAxis
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Pension Plans, Defined Benefit [Member] | U.S. common stocks [Member] | Fair Value, Inputs, Level 2 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Pension Plans, Defined Benefit [Member] | U.S. treasury notes and bonds [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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[1]  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | U.S. treasury notes and bonds [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 203.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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[1]  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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[1]  
Pension Plans, Defined Benefit [Member] | U.S. treasury notes and bonds [Member] | Fair Value, Inputs, Level 2 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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[1]  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Mortgage-backed securities      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 20.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Mortgage-backed securities | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Mortgage-backed securities | Fair Value, Inputs, Level 2 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 20.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Corporate fixed income and other securities [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 167.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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[2]  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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[2]  
Pension Plans, Defined Benefit [Member] | Corporate fixed income and other securities [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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[2]  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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[2]  
Pension Plans, Defined Benefit [Member] | Corporate fixed income and other securities [Member] | Fair Value, Inputs, Level 2 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 167.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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[2]  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 167.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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[2]  
Pension Plans, Defined Benefit [Member] | Mortgage-backed securities [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 19.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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[2]  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 19.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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[2]  
Pension Plans, Defined Benefit [Member] | Mortgage-backed securities [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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[2]  
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 3.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 0.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Receivable (foreign currency) [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending (15.6)us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Payable (foreign currency) [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Total Plan investments [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 705.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Total Plan investments [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 437.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
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Pension Plans, Defined Benefit [Member] | Total Plan investments [Member] | Fair Value, Inputs, Level 2 [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 268.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 268.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Plans, Defined Benefit [Member] | Receivable from broker for securities sold [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 3.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 3.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Plans, Defined Benefit [Member] | Interest and dividends receivable [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 3.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets 3.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Plans, Defined Benefit [Member] | Payable to broker for securities purchased [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending (33.0)us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets (33.0)us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
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Pension Plans, Defined Benefit [Member] | Total Plan assets [Member]      
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]      
Fair Value of Plan Assets, Ending 679.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ invest_InvestmentSecuritiesSeriesAxis
= oge_TotalPlanAssetsMember
654.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ invest_InvestmentSecuritiesSeriesAxis
= oge_TotalPlanAssetsMember
 
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Fair Value of Plan Assets $ 679.8us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ invest_InvestmentSecuritiesSeriesAxis
= oge_TotalPlanAssetsMember
$ 654.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_PensionPlansDefinedBenefitMember
/ invest_InvestmentSecuritiesSeriesAxis
= oge_TotalPlanAssetsMember
 
Less Than 90% [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Projected Benefit Obligation Funded Status Thresholds Fixed Income 50.00%oge_ProjectedBenefitObligationFundedStatusThresholdsFixedIncome
/ us-gaap_FairValueByAssetClassAxis
= oge_LessThan90Member
   
Projected Benefit Obligation Funded Status Thresholds Equity 50.00%oge_ProjectedBenefitObligationFundedStatusThresholdsEquity
/ us-gaap_FairValueByAssetClassAxis
= oge_LessThan90Member
   
Projected Benefit Obligation Funded Status Thresholds 100.00%oge_ProjectedBenefitObligationFundedStatusThresholds
/ us-gaap_FairValueByAssetClassAxis
= oge_LessThan90Member
   
95% [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Projected Benefit Obligation Funded Status Thresholds Fixed Income 58.00%oge_ProjectedBenefitObligationFundedStatusThresholdsFixedIncome
/ us-gaap_FairValueByAssetClassAxis
= oge_A95Member
   
Projected Benefit Obligation Funded Status Thresholds Equity 42.00%oge_ProjectedBenefitObligationFundedStatusThresholdsEquity
/ us-gaap_FairValueByAssetClassAxis
= oge_A95Member
   
Projected Benefit Obligation Funded Status Thresholds 100.00%oge_ProjectedBenefitObligationFundedStatusThresholds
/ us-gaap_FairValueByAssetClassAxis
= oge_A95Member
   
100% [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Projected Benefit Obligation Funded Status Thresholds Fixed Income 65.00%oge_ProjectedBenefitObligationFundedStatusThresholdsFixedIncome
/ us-gaap_FairValueByAssetClassAxis
= oge_A100Member
   
Projected Benefit Obligation Funded Status Thresholds Equity 35.00%oge_ProjectedBenefitObligationFundedStatusThresholdsEquity
/ us-gaap_FairValueByAssetClassAxis
= oge_A100Member
   
Projected Benefit Obligation Funded Status Thresholds 100.00%oge_ProjectedBenefitObligationFundedStatusThresholds
/ us-gaap_FairValueByAssetClassAxis
= oge_A100Member
   
105% [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Projected Benefit Obligation Funded Status Thresholds Fixed Income 73.00%oge_ProjectedBenefitObligationFundedStatusThresholdsFixedIncome
/ us-gaap_FairValueByAssetClassAxis
= oge_A105Member
   
Projected Benefit Obligation Funded Status Thresholds Equity 27.00%oge_ProjectedBenefitObligationFundedStatusThresholdsEquity
/ us-gaap_FairValueByAssetClassAxis
= oge_A105Member
   
Projected Benefit Obligation Funded Status Thresholds 100.00%oge_ProjectedBenefitObligationFundedStatusThresholds
/ us-gaap_FairValueByAssetClassAxis
= oge_A105Member
   
110% [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Projected Benefit Obligation Funded Status Thresholds Fixed Income 80.00%oge_ProjectedBenefitObligationFundedStatusThresholdsFixedIncome
/ us-gaap_FairValueByAssetClassAxis
= oge_A110Member
   
Projected Benefit Obligation Funded Status Thresholds Equity 20.00%oge_ProjectedBenefitObligationFundedStatusThresholdsEquity
/ us-gaap_FairValueByAssetClassAxis
= oge_A110Member
   
Projected Benefit Obligation Funded Status Thresholds 100.00%oge_ProjectedBenefitObligationFundedStatusThresholds
/ us-gaap_FairValueByAssetClassAxis
= oge_A110Member
   
115% [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Projected Benefit Obligation Funded Status Thresholds Fixed Income 85.00%oge_ProjectedBenefitObligationFundedStatusThresholdsFixedIncome
/ us-gaap_FairValueByAssetClassAxis
= oge_A115Member
   
Projected Benefit Obligation Funded Status Thresholds Equity 15.00%oge_ProjectedBenefitObligationFundedStatusThresholdsEquity
/ us-gaap_FairValueByAssetClassAxis
= oge_A115Member
   
Projected Benefit Obligation Funded Status Thresholds 100.00%oge_ProjectedBenefitObligationFundedStatusThresholds
/ us-gaap_FairValueByAssetClassAxis
= oge_A115Member
   
120% [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Projected Benefit Obligation Funded Status Thresholds Fixed Income 90.00%oge_ProjectedBenefitObligationFundedStatusThresholdsFixedIncome
/ us-gaap_FairValueByAssetClassAxis
= oge_A120Member
   
Projected Benefit Obligation Funded Status Thresholds Equity 10.00%oge_ProjectedBenefitObligationFundedStatusThresholdsEquity
/ us-gaap_FairValueByAssetClassAxis
= oge_A120Member
   
Projected Benefit Obligation Funded Status Thresholds 100.00%oge_ProjectedBenefitObligationFundedStatusThresholds
/ us-gaap_FairValueByAssetClassAxis
= oge_A120Member
   
Domestic All-Cap/Large Cap Equity [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Target Plan Asset Allocations 50.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticAllCaplargeCapEquityMember
   
Target Plan Asset Allocations Range Minimum 50.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMinimum
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticAllCaplargeCapEquityMember
   
Target Plan Asset Allocations Range Maximum 60.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMaximum
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticAllCaplargeCapEquityMember
   
Domestic Mid-Cap Equity [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Target Plan Asset Allocations 15.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticMidCapEquityMember
   
Target Plan Asset Allocations Range Minimum 5.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMinimum
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticMidCapEquityMember
   
Target Plan Asset Allocations Range Maximum 25.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMaximum
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticMidCapEquityMember
   
Domestic Small-Cap Equity [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Target Plan Asset Allocations 15.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticSmallCapEquityMember
   
Target Plan Asset Allocations Range Minimum 5.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMinimum
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticSmallCapEquityMember
   
Target Plan Asset Allocations Range Maximum 25.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMaximum
/ us-gaap_FairValueByAssetClassAxis
= oge_DomesticSmallCapEquityMember
   
International Equity [Member]      
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]      
Target Plan Asset Allocations 20.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations
/ us-gaap_FairValueByAssetClassAxis
= oge_InternationalEquityMember
   
Target Plan Asset Allocations Range Minimum 10.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMinimum
/ us-gaap_FairValueByAssetClassAxis
= oge_InternationalEquityMember
   
Target Plan Asset Allocations Range Maximum 30.00%us-gaap_DefinedBenefitPlanTargetPlanAssetAllocationsRangeMaximum
/ us-gaap_FairValueByAssetClassAxis
= oge_InternationalEquityMember
   
[1] This category represents U.S. treasury notes and bonds with a Moody's Investors Services rating of Aaa and Government Agency Bonds with a Moody's Investors Services rating of A1 or higher.
[2] This category primarily represents U.S. corporate bonds with an investment grade rating at or above Baa3 or BBB- by Moody's Investors Services, Standard & Poor's Ratings Services or Fitch Ratings.
[3] This category represents units of participation in a commingled fund that primarily invested in stocks of international companies and emerging markets.
[4] This category represents units of participation in an investment pool which primarily invests in foreign or domestic bonds, debentures, mortgages, equipment or other trust certificates, notes, obligations issued or guaranteed by the U.S. Government or its agencies, bank certificates of deposit, bankers' acceptances and repurchase agreements, high grade commercial paper and other instruments with money market characteristics with a fixed or variable interest rate. There are no restrictions on redemptions in the common/collective trust.