XML 22 R57.htm IDEA: XBRL DOCUMENT v2.4.1.9
Retirement Plans and Postretirement Benefit Plans 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]      
Fair Value of Plan Assets $ 59.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets $ 61.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets  
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]      
Level 3 Asset Value, Beginning of Period 53.1us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue    
Unrealized Gains 1.5ogec_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisUnrealizedGains    
Interest Income 1.0ogec_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisInterestIncome    
Dividend Income 0.6ogec_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisDividends    
Realized Gains (0.9)ogec_FairValueMeasurementwithUnobservableInputsReconciliationRecurringBasisRealizedGainsLosses    
Claims Paid (4.3)ogec_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisClaimsPaid    
Level 3 Asset Value, End of Period 51.0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue    
Postretirement Plan, Expected Future Benefit Payments in Year One 12.8ogec_PostretirementPlanExpectedFutureBenefitPaymentsInYearOne    
Postretirement Plan, Expected Future Benefit Payments in Year Two 13.1ogec_PostretirementPlanExpectedFutureBenefitPaymentsInYearTwo    
Postretirement Plan, Expected Future Benefit Payments in Year Three 13.3ogec_PostretirementPlanExpectedFutureBenefitPaymentsInYearThree    
Postretirement Plan, Expected Future Benefit Payments in Year Four 13.5ogec_PostretirementPlanExpectedFutureBenefitPaymentsInYearFour    
Postretirement Plan, Expected Future Benefit Payments in Year Five 13.7ogec_PostretirementPlanExpectedFutureBenefitPaymentsInYearFive    
Postretirement Plan, Expected Future Benefit Payments Thereafter 67.6ogec_PostretirementPlanExpectedFutureBenefitPaymentsThereafter    
Postemployment Benefits Liability 1.1us-gaap_PostemploymentBenefitsLiabilityCurrentAndNoncurrent 1.4us-gaap_PostemploymentBenefitsLiabilityCurrentAndNoncurrent  
Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 8.6us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 8.3us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		  
Fair Value, Inputs, Level 3 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 51.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member		 53.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member		  
Group Retiree Medical Insurance Contract [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 51.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_GroupRetireeMedicalInsuranceContractMember		 [1] 53.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_GroupRetireeMedicalInsuranceContractMember		 [1]  
Plan investments attributable to affiliates (5.4)ogec_PlanInvestmentsAttributableToAffiliates
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_GroupRetireeMedicalInsuranceContractMember		 (4.7)ogec_PlanInvestmentsAttributableToAffiliates
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_GroupRetireeMedicalInsuranceContractMember		  
Group Retiree Medical Insurance Contract [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_GroupRetireeMedicalInsuranceContractMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 [1] 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_GroupRetireeMedicalInsuranceContractMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 [1]  
Group Retiree Medical Insurance Contract [Member] | Fair Value, Inputs, Level 3 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 51.0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_GroupRetireeMedicalInsuranceContractMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member		 [1] 53.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_GroupRetireeMedicalInsuranceContractMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member		 [1]  
U.S. Equity Mutual Funds Investment [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 8.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_USEquityMutualFundsInvestmentMember		 7.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_USEquityMutualFundsInvestmentMember		  
U.S. Equity Mutual Funds Investment [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 8.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_USEquityMutualFundsInvestmentMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 7.9us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_USEquityMutualFundsInvestmentMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		  
U.S. Equity Mutual Funds Investment [Member] | Fair Value, Inputs, Level 3 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_USEquityMutualFundsInvestmentMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member		 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= ogec_USEquityMutualFundsInvestmentMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member		  
Money Market Funds [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 0.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember		 0.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember		  
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 0.1us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		 0.4us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member		  
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member		 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis
= us-gaap_MoneyMarketFundsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member		  
Other Postretirement Benefit Plans, Defined Benefit [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Benefit Obligation 217.6us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember		 202.4us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember		 236.4us-gaap_DefinedBenefitPlanBenefitObligation
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Fair Value of Plan Assets 54.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember		 56.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember		 55.5us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Funded Status of Plan (163.4)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember		 (145.7)us-gaap_DefinedBenefitPlanFundedStatusOfPlan
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember		  
Defined Benefit Plan, 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
Other Postretirement Benefit Plans, Defined Benefit [Member] | Fair Value, Inputs, Level 2 [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member		 0us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member		  
OG&E [Member]      
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]      
Fair Value of Plan Assets $ 54.2us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ dei_LegalEntityAxis
= ogec_OgAndEMember		 $ 56.7us-gaap_DefinedBenefitPlanFairValueOfPlanAssets
/ dei_LegalEntityAxis
= ogec_OgAndEMember		  
[1] This category represents a group retiree medical insurance contract which invests in a pool of common stocks, bonds and money market accounts, of which a significant portion is comprised of mortgage-backed securities.