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Organization, Basis of Presentation and Significant Accounting Policies (Details 4)
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Annual Composite Depreciation Rate      
Annual Composite Depreciation Rate 2.50%us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService 2.60%us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService 2.50%us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService
FES      
Annual Composite Depreciation Rate      
Annual Composite Depreciation Rate 3.10%us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService
/ dei_LegalEntityAxis
= fe_FesMember		 3.10%us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService
/ dei_LegalEntityAxis
= fe_FesMember		 3.10%us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService
/ dei_LegalEntityAxis
= fe_FesMember