2.4.0.8401310 - Disclosure - Fair Value Measurements and Credit Concentration (Net Assets and Liabilities Measured on Recurring Basis Level 3 Significant Unobservable Inputs) (Details)truefalseIn Millions, unless otherwise specifiedfalse1false falsefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00PureStandardhttp://www.xbrl.org/2003/instancepurexbrli02false falsefalseFROM_Jan01_2012_TO_Dec31_2012_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2012-01-01T00:00:002012-12-31T00:00:00PureStandardhttp://www.xbrl.org/2003/instancepurexbrli01false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse1false USDtruefalse$AS_OF_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseRetail Natural Gas Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_RetailNaturalGasContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Energy Commodities, Net [Member] | Retail Natural Gas Sales Contracts [Member]2true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]3false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse3600000036[1]USD$falsetruefalse2truefalsefalse2400000024[1]USD$falsetruefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)4true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]5false 4ppl_FairValueToDeliverNextTwelveMonthsppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1600000016USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the fair value scheduled to deliver within the next 12 months.No definition available.false2Fair value scheduled to deliver within next 12 months6false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseRetail Natural Gas Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_RetailNaturalGasContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Retail Natural Gas Sales Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member]7true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]8false 5ppl_FairValueInputsWholesalePriceForRetailDeliveryPointsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse1.001.00[2]falsefalsefalse2truetruefalse1.001.00[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by internally developed models that project forward prices at a location where pricing is unobservable or the delivery dates are beyond the dates for which independent quotes are available, used as an input to measure fair value.No definition available.false0Observable wholesale prices used as proxy for retail delivery points9false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse5false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseRetail Natural Gas Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_RetailNaturalGasContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Retail Natural Gas Sales Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member]10true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]11false 5ppl_FairValueInputsWholesalePriceForRetailDeliveryPointsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.170.17[2]falsefalsefalse2truetruefalse0.210.21[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by internally developed models that project forward prices at a location where pricing is unobservable or the delivery dates are beyond the dates for which independent quotes are available, used as an input to measure fair value.No definition available.false0Observable wholesale prices used as proxy for retail delivery points12false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse7false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseRetail Natural Gas Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_RetailNaturalGasContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Retail Natural Gas Sales Contracts [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]13true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]14false 5ppl_FairValueInputsWholesalePriceForRetailDeliveryPointsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.820.82[2]falsefalsefalse2truetruefalse0.750.75[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by internally developed models that project forward prices at a location where pricing is unobservable or the delivery dates are beyond the dates for which independent quotes are available, used as an input to measure fair value.No definition available.false0Observable wholesale prices used as proxy for retail delivery points15false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse9false USDtruefalse$AS_OF_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_ElectricContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalsePower Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_ElectricContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Energy Commodities, Net [Member] | Power Sales Contracts [Member]16true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]17false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-5000000-5[3]USD$falsefalsefalse2truefalsefalse-4000000-4[3]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)18true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]19false 4ppl_FairValueToDeliverNextTwelveMonthsppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-5000000-5USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the fair value scheduled to deliver within the next 12 months.No definition available.false2Fair value scheduled to deliver within next 12 months20false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse11false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_ElectricContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalsePower Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_ElectricContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Power Sales Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member]21true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]22false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse1.001.00[2]falsefalsefalse2truetruefalse0.240.24[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices23false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse13false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_ElectricContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalsePower Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_ElectricContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Power Sales Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member]24true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]25false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.110.11[2]falsefalsefalse2truetruefalse0.240.24[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices26false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse15false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_ElectricContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalsePower Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_ElectricContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Power Sales Contracts [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]27true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]28false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.390.39[2]falsefalsefalse2truetruefalse0.240.24[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices29false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse17false USDtruefalse$AS_OF_Dec31_2012_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_FinancialTransmissionRightsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2012-12-31T00:00:000001-01-01T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseFinancial Transmission Rights Purchase Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_FinancialTransmissionRightsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Energy Commodities, Net [Member] | Financial Transmission Rights Purchase Contracts [Member]30true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]31false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse20000002[4]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)32false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse18false truefalseFROM_Jan01_2012_TO_Dec31_2012_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_FinancialTransmissionRightsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2012-01-01T00:00:002012-12-31T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseFinancial Transmission Rights Purchase Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_FinancialTransmissionRightsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Financial Transmission Rights Purchase Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member]33true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]34false 5ppl_FairValueInputsHistoricalSettledPricesUsedToModelForwardPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truetruefalse1.001.00[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by historical settled prices used to model forward prices.No definition available.false0Historical settled prices used to model forward prices35false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse19false truefalseFROM_Jan01_2012_TO_Dec31_2012_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_FinancialTransmissionRightsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2012-01-01T00:00:002012-12-31T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseFinancial Transmission Rights Purchase Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_FinancialTransmissionRightsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Financial Transmission Rights Purchase Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member]36true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]37false 5ppl_FairValueInputsHistoricalSettledPricesUsedToModelForwardPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truetruefalse1.001.00[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by historical settled prices used to model forward prices.No definition available.false0Historical settled prices used to model forward prices38false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse20false truefalseFROM_Jan01_2012_TO_Dec31_2012_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_FinancialTransmissionRightsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2012-01-01T00:00:002012-12-31T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseFinancial Transmission Rights Purchase Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_FinancialTransmissionRightsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Financial Transmission Rights Purchase Contracts [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]39true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]40false 5ppl_FairValueInputsHistoricalSettledPricesUsedToModelForwardPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truetruefalse1.001.00[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by historical settled prices used to model forward prices.No definition available.false0Historical settled prices used to model forward prices41false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse21false USDtruefalse$AS_OF_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_HeatRateCallOptionMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseHeat Rate Call Option [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_HeatRateCallOptionMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Energy Commodities, Net [Member] | Heat Rate Call Option [Member]42true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]43false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse90000009[5]USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)44true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]45false 4ppl_FairValueToDeliverNextTwelveMonthsppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse60000006USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the fair value scheduled to deliver within the next 12 months.No definition available.false2Fair value scheduled to deliver within next 12 months46false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse22false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_HeatRateCallOptionMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseHeat Rate Call Option [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_HeatRateCallOptionMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Heat Rate Call Option [Member] | Discounted Cash Flow [Member] | Maximum [Member]47true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]48false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.180.18[2]falsefalsefalse2falsefalsefalse00falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices49false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse23false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_HeatRateCallOptionMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseHeat Rate Call Option [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_HeatRateCallOptionMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Heat Rate Call Option [Member] | Discounted Cash Flow [Member] | Minimum [Member]50true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]51false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.180.18[2]falsefalsefalse2falsefalsefalse00falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices52false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse24false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_HeatRateCallOptionMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseHeat Rate Call Option [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_HeatRateCallOptionMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Energy Commodities, Net [Member] | Heat Rate Call Option [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]53true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]54false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.180.18[2]falsefalsefalse2falsefalsefalse00falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices55false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse25false USDtruefalse$AS_OF_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_AuctionRateSecuritiesMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseAuction Rate Securities [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AuctionRateSecuritiesMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberIntegerStandardhttp://pplweb.com/20130630Integerppl0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Auction Rate Securities [Member]56true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]57false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1900000019[6]USD$falsefalsefalse2truefalsefalse1600000016[6]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)58true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]59false 4ppl_WeightedAverageOfContractualMaturitiesAuctionRateSecuritiesppl_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2323falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:integerItemTypeintegerWeighted average contractual maturities (in years) of auction rate securities.No definition available.false256Weighted average contractual maturity of auction rate securites (in years)60false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse27false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_AuctionRateSecuritiesMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseAuction Rate Securities [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AuctionRateSecuritiesMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Auction Rate Securities [Member] | Discounted Cash Flow [Member] | Maximum [Member]61true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]62false 5ppl_FairValueInputsModeledFromSecuritiesIndustryAndFinancialMarketsAssociationIndexppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.780.78[2]falsefalsefalse2truetruefalse0.740.74[2]falsefalsefalsenum:percentItemTypepureThe percent of unobservable inputs represented by estimated forward rates of a specific index, used as an input to measure fair value.No definition available.false0Modeled from SIFMA Index63false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse29false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_AuctionRateSecuritiesMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseAuction Rate Securities [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AuctionRateSecuritiesMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Auction Rate Securities [Member] | Discounted Cash Flow [Member] | Minimum [Member]64true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]65false 5ppl_FairValueInputsModeledFromSecuritiesIndustryAndFinancialMarketsAssociationIndexppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.110.11[2]falsefalsefalse2truetruefalse0.540.54[2]falsefalsefalsenum:percentItemTypepureThe percent of unobservable inputs represented by estimated forward rates of a specific index, used as an input to measure fair value.No definition available.false0Modeled from SIFMA Index66false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse31false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_AuctionRateSecuritiesMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseAuction Rate Securities [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AuctionRateSecuritiesMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Auction Rate Securities [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]67true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]68false 5ppl_FairValueInputsModeledFromSecuritiesIndustryAndFinancialMarketsAssociationIndexppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.630.63[2]falsefalsefalse2truetruefalse0.640.64[2]falsefalsefalsenum:percentItemTypepureThe percent of unobservable inputs represented by estimated forward rates of a specific index, used as an input to measure fair value.No definition available.false0Modeled from SIFMA Index69false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse33false USDtruefalse$AS_OF_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_CrossCurrencyInterestRateContractMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseCross Currency Swaps [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CrossCurrencyInterestRateContractMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cross Currency Swaps [Member]70true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]71false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse30000003[7]USD$falsefalsefalse2truefalsefalse10000001[7]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)72false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse35false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_CrossCurrencyInterestRateContractMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseCross Currency Swaps [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CrossCurrencyInterestRateContractMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Cross Currency Swaps [Member] | Discounted Cash Flow [Member] | Maximum [Member]73true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]74false 5us-gaap_FairValueInputsEntityCreditRiskus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.110.11[2]falsefalsefalse2truetruefalse0.220.22[2]falsefalsefalsenum:percentItemTypepureRisk associated with risk of default, credit spread risk and downgrade risk, expressed as a percentage, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false0Credit valuation adjustment75false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse37false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_CrossCurrencyInterestRateContractMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseCross Currency Swaps [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CrossCurrencyInterestRateContractMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Cross Currency Swaps [Member] | Discounted Cash Flow [Member] | Minimum [Member]76true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]77false 5us-gaap_FairValueInputsEntityCreditRiskus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.110.11[2]falsefalsefalse2truetruefalse0.220.22[2]falsefalsefalsenum:percentItemTypepureRisk associated with risk of default, credit spread risk and downgrade risk, expressed as a percentage, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false0Credit valuation adjustment78false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse39false truefalseFROM_Jan01_2013_TO_Jun30_2013_ppl_FairValueByAssetLiabilityClassAxis_CrossCurrencyInterestRateContractMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseCross Currency Swaps [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CrossCurrencyInterestRateContractMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0Cross Currency Swaps [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]79true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]80false 5us-gaap_FairValueInputsEntityCreditRiskus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.110.11[2]falsefalsefalse2truetruefalse0.220.22[2]falsefalsefalsenum:percentItemTypepureRisk associated with risk of default, credit spread risk and downgrade risk, expressed as a percentage, used as an input to measure fair value.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false0Credit valuation adjustment81false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse41false USDtruefalse$AS_OF_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseRetail Natural Gas Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_RetailNaturalGasContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Retail Natural Gas Sales Contracts [Member]82true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]83false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse3600000036[1]USD$falsefalsefalse2truefalsefalse2400000024[1]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)84true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]85false 4ppl_FairValueToDeliverNextTwelveMonthsppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1600000016USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the fair value scheduled to deliver within the next 12 months.No definition available.false2Fair value scheduled to deliver within next 12 months86false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse43false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseRetail Natural Gas Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_RetailNaturalGasContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Retail Natural Gas Sales Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member]87true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]88false 5ppl_FairValueInputsWholesalePriceForRetailDeliveryPointsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse1.001.00[2]falsefalsefalse2truetruefalse1.001.00[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by internally developed models that project forward prices at a location where pricing is unobservable or the delivery dates are beyond the dates for which independent quotes are available, used as an input to measure fair value.No definition available.false0Observable wholesale prices used as proxy for retail delivery points89false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse45false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseRetail Natural Gas Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_RetailNaturalGasContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Retail Natural Gas Sales Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member]90true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]91false 5ppl_FairValueInputsWholesalePriceForRetailDeliveryPointsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.170.17[2]falsefalsefalse2truetruefalse0.210.21[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by internally developed models that project forward prices at a location where pricing is unobservable or the delivery dates are beyond the dates for which independent quotes are available, used as an input to measure fair value.No definition available.false0Observable wholesale prices used as proxy for retail delivery points92false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse47false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_RetailNaturalGasContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseRetail Natural Gas Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_RetailNaturalGasContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Retail Natural Gas Sales Contracts [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]93true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]94false 5ppl_FairValueInputsWholesalePriceForRetailDeliveryPointsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.820.82[2]falsefalsefalse2truetruefalse0.750.75[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by internally developed models that project forward prices at a location where pricing is unobservable or the delivery dates are beyond the dates for which independent quotes are available, used as an input to measure fair value.No definition available.false0Observable wholesale prices used as proxy for retail delivery points95false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse49false USDtruefalse$AS_OF_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_ElectricContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalsePower Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_ElectricContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Power Sales Contracts [Member]96true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]97false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-5000000-5[3]USD$falsefalsefalse2truefalsefalse-4000000-4[3]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)98true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]99false 4ppl_FairValueToDeliverNextTwelveMonthsppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-5000000-5USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the fair value scheduled to deliver within the next 12 months.No definition available.false2Fair value scheduled to deliver within next 12 months100false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse51false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_ElectricContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalsePower Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_ElectricContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Power Sales Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member]101true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]102false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse1.001.00[2]falsefalsefalse2truetruefalse0.240.24[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices103false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse53false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_ElectricContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalsePower Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_ElectricContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Power Sales Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member]104true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]105false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.110.11[2]falsefalsefalse2truetruefalse0.240.24[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices106false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse55false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_ElectricContractsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalsePower Sales Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_ElectricContractsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Power Sales Contracts [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]107true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]108false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.390.39[2]falsefalsefalse2truetruefalse0.240.24[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices109false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse57false USDtruefalse$AS_OF_Dec31_2012_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_FinancialTransmissionRightsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2012-12-31T00:00:000001-01-01T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseFinancial Transmission Rights Purchase Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_FinancialTransmissionRightsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Financial Transmission Rights Purchase Contracts [Member]110true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]111false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse20000002[4]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)112false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse58false truefalseFROM_Jan01_2012_TO_Dec31_2012_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_FinancialTransmissionRightsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2012-01-01T00:00:002012-12-31T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseFinancial Transmission Rights Purchase Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_FinancialTransmissionRightsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Financial Transmission Rights Purchase Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member]113true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]114false 5ppl_FairValueInputsHistoricalSettledPricesUsedToModelForwardPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truetruefalse1.001.00[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by historical settled prices used to model forward prices.No definition available.false0Historical settled prices used to model forward prices115false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse59false truefalseFROM_Jan01_2012_TO_Dec31_2012_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_FinancialTransmissionRightsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2012-01-01T00:00:002012-12-31T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseFinancial Transmission Rights Purchase Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_FinancialTransmissionRightsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Financial Transmission Rights Purchase Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member]116true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]117false 5ppl_FairValueInputsHistoricalSettledPricesUsedToModelForwardPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truetruefalse1.001.00[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by historical settled prices used to model forward prices.No definition available.false0Historical settled prices used to model forward prices118false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse60false truefalseFROM_Jan01_2012_TO_Dec31_2012_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_FinancialTransmissionRightsMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2012-01-01T00:00:002012-12-31T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseFinancial Transmission Rights Purchase Contracts [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_FinancialTransmissionRightsMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Financial Transmission Rights Purchase Contracts [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]119true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]120false 5ppl_FairValueInputsHistoricalSettledPricesUsedToModelForwardPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truetruefalse1.001.00[2]falsefalsefalsenum:percentItemTypepureThe percent of fair value due to unobservable inputs represented by historical settled prices used to model forward prices.No definition available.false0Historical settled prices used to model forward prices121false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse61false USDtruefalse$AS_OF_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_HeatRateCallOptionMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseHeat Rate Call Option [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_HeatRateCallOptionMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Heat Rate Call Option [Member]122true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]123false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse90000009[5]USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)124true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]125false 4ppl_FairValueToDeliverNextTwelveMonthsppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse60000006USD$falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of the fair value scheduled to deliver within the next 12 months.No definition available.false2Fair value scheduled to deliver within next 12 months126false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse62false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_HeatRateCallOptionMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseHeat Rate Call Option [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_HeatRateCallOptionMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Heat Rate Call Option [Member] | Discounted Cash Flow [Member] | Maximum [Member]127true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]128false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.180.18[2]falsefalsefalse2falsefalsefalse00falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices129false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse63false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_HeatRateCallOptionMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseHeat Rate Call Option [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_HeatRateCallOptionMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Heat Rate Call Option [Member] | Discounted Cash Flow [Member] | Minimum [Member]130true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]131false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.180.18[2]falsefalsefalse2falsefalsefalse00falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices132false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse64false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_DerivativeFinancialInstrumentsAssetsMember_ppl_FairValueByAssetLiabilityOtherClassAxis_HeatRateCallOptionMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseEnergy Commodities, Net [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DerivativeFinancialInstrumentsAssetsMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseHeat Rate Call Option [Member]ppl_FairValueByAssetLiabilityOtherClassAxisxbrldihttp://xbrl.org/2006/xbrldippl_HeatRateCallOptionMemberppl_FairValueByAssetLiabilityOtherClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Energy Commodities, Net [Member] | Heat Rate Call Option [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]133true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]134false 5ppl_FairValueInputsProprietaryModelForwardBasisPricesppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.180.18[2]falsefalsefalse2falsefalsefalse00falsefalsefalsenum:percentItemTypepureThe percent of fair value determined by the use of a proprietary model to calculate forward basis prices.No definition available.false0Proprietary model used to calculate forward basis prices135false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse65false USDtruefalse$AS_OF_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_AuctionRateSecuritiesMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMemberhttp://www.sec.gov/CIK0000922224instant2013-06-30T00:00:000001-01-01T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseAuction Rate Securities [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AuctionRateSecuritiesMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberIntegerStandardhttp://pplweb.com/20130630Integerppl0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0PPL Energy Supply LLC [Member] | Auction Rate Securities [Member]136true 3ppl_FairValueInputsAssetsLiabilitiesQuantitativeInformationLineItemsppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]137false 4ppl_AssetsLiabilitiesFairValueDisclosureppl_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1600000016[6]USD$falsetruefalse2truefalsefalse1300000013[6]USD$falsetruefalsexbrli:monetaryItemTypemonetaryThis element represents the aggregate of the assets and liabilities reported on the balance sheet at period end measured at fair value by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.No definition available.false2Fair value of net asset and (liability)138true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]139false 4ppl_WeightedAverageOfContractualMaturitiesAuctionRateSecuritiesppl_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2323falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:integerItemTypeintegerWeighted average contractual maturities (in years) of auction rate securities.No definition available.false256Weighted average contractual maturity of auction rate securites (in years)140false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse67false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_AuctionRateSecuritiesMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MaximumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseAuction Rate Securities [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AuctionRateSecuritiesMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMaximum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MaximumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Auction Rate Securities [Member] | Discounted Cash Flow [Member] | Maximum [Member]141true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]142false 5ppl_FairValueInputsModeledFromSecuritiesIndustryAndFinancialMarketsAssociationIndexppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.780.78[2]falsefalsefalse2truetruefalse0.740.74[2]falsefalsefalsenum:percentItemTypepureThe percent of unobservable inputs represented by estimated forward rates of a specific index, used as an input to measure fair value.No definition available.false0Modeled from SIFMA Index143false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse69false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_AuctionRateSecuritiesMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_MinimumMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseAuction Rate Securities [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AuctionRateSecuritiesMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseMinimum [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_MinimumMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Auction Rate Securities [Member] | Discounted Cash Flow [Member] | Minimum [Member]144true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]145false 5ppl_FairValueInputsModeledFromSecuritiesIndustryAndFinancialMarketsAssociationIndexppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.110.11[2]falsefalsefalse2truetruefalse0.570.57[2]falsefalsefalsenum:percentItemTypepureThe percent of unobservable inputs represented by estimated forward rates of a specific index, used as an input to measure fair value.No definition available.false0Modeled from SIFMA Index146false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse71false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_PplEnergySupplyLLCMember_ppl_FairValueByAssetLiabilityClassAxis_AuctionRateSecuritiesMember_us-gaap_FairValueByFairValueHierarchyLevelAxis_FairValueInputsLevel3Member_us-gaap_FairValueByMeasurementFrequencyAxis_FairValueMeasurementsRecurringMember_us-gaap_RangeAxis_WeightedAverageMember_us-gaap_ValuationTechniqueAxis_IncomeApproachValuationTechniqueMemberhttp://www.sec.gov/CIK0000922224duration2013-01-01T00:00:002013-06-30T00:00:00falsefalsePPL Energy Supply LLC [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_PplEnergySupplyLLCMemberdei_LegalEntityAxisexplicitMemberfalsefalseRecurring [Member]us-gaap_FairValueByMeasurementFrequencyAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueMeasurementsRecurringMemberus-gaap_FairValueByMeasurementFrequencyAxisexplicitMemberfalsefalseLevel 3 [Member]us-gaap_FairValueByFairValueHierarchyLevelAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueInputsLevel3Memberus-gaap_FairValueByFairValueHierarchyLevelAxisexplicitMemberfalsefalseAuction Rate Securities [Member]ppl_FairValueByAssetLiabilityClassAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AuctionRateSecuritiesMemberppl_FairValueByAssetLiabilityClassAxisexplicitMemberfalsefalseDiscounted Cash Flow [Member]us-gaap_ValuationTechniqueAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_IncomeApproachValuationTechniqueMemberus-gaap_ValuationTechniqueAxisexplicitMemberfalsefalseWeighted Average [Member]us-gaap_RangeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_WeightedAverageMemberus-gaap_RangeAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0PPL Energy Supply LLC [Member] | Auction Rate Securities [Member] | Discounted Cash Flow [Member] | Weighted Average [Member]147true 4us-gaap_FairValueInputsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Fair Value Inputs [Abstract]148false 5ppl_FairValueInputsModeledFromSecuritiesIndustryAndFinancialMarketsAssociationIndexppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.620.62[2]falsefalsefalse2truetruefalse0.650.65[2]falsefalsefalsenum:percentItemTypepureThe percent of unobservable inputs represented by estimated forward rates of a specific index, used as an input to measure fair value.No definition available.false0Modeled from SIFMA Index1At June 30, 2013, retail natural gas sales contracts extend through 2018, and $16 million of the fair value is scheduled to deliver within the next 12 months. As the forward price of natural gas increases/(decreases), the fair value of the contracts (decreases)/increases.2For energy commodities and auction rate securities, the range and weighted average represent the percentage of fair value derived from the unobservable inputs. For cross-currency swaps, the range and weighted average represent the percentage decrease in fair value due to the unobservable inputs used in the model to calculate the credit valuation adjustment.3At June 30, 2013, power sales contracts extend into 2018, and $(5) million of the fair value is scheduled to deliver within the next 12 months. As the forward price of basis increases/(decreases), the fair value of the contracts (decreases)/increases.4As the forward implied spread increases/(decreases), the fair value of the contracts increases/(decreases).5At June 30, 2013, the heat rate call option extends through 2014, and $6 million of the fair value is scheduled to deliver within the next 12 months. As the market implied heat rate increases/(decreases), the fair value of the contracts increases/(decreases).6At June 30, 2013, auction rate securities have a weighted average contractual maturity of 23 years. The model used to calculate fair value incorporates an assumption that the auctions will continue to fail. As the modeled forward rates of the SIFMA Index increase/(decrease), the fair value of the securities increases/(decreases).7At June 30, 2013, cross-currency swaps extend into 2021. The credit valuation adjustment incorporates projected probabilities of default and estimated recovery rates. As the credit valuation adjustment increases/(decreases), the fair value of the swaps (decreases)/increases.falseFair Value Measurements and Credit Concentration (Net Assets and Liabilities Measured on Recurring Basis Level 3 Significant Unobservable Inputs) (Details) (Recurring [Member], Level 3 [Member], USD $)MillionsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://pplweb.com/role/DisclosureFairValueMeasurementsAndCreditConcentrationNetAssetsAndLiabilitiesMeasuredOnRecurringBasisLevel3SignificantUnobservableInputsDetails2148