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Includes the type of instrument hedged, contract amount, term, and so forth.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579240-113959 false0Hedged items in fair value hedging relationships4false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse3false USDtruefalse$FROM_Apr01_2012_TO_Jun30_2012_us-gaap_DerivativeInstrumentRiskAxis_InterestRateSwapMember_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_FairValueHedgingMember_us-gaap_IncomeStatementLocationAxis_InterestExpenseMemberhttp://www.sec.gov/CIK0000922224duration2012-04-01T00:00:002012-06-30T00:00:00falsefalseFair Value Hedges [Member]us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_FairValueHedgingMemberus-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisexplicitMemberfalsefalseInterest Rate Swaps [Member]us-gaap_DerivativeInstrumentRiskAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestRateSwapMemberus-gaap_DerivativeInstrumentRiskAxisexplicitMemberfalsefalseInterest Expense [Member]us-gaap_IncomeStatementLocationAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestExpenseMemberus-gaap_IncomeStatementLocationAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Fair Value Hedges [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]5true 4ppl_AmountsIncludedInIncomeStatementOrOtherComprehensiveIncomeAbstractppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]6false 5us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeNetus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2truefalsefalse10000001USD$falsetruefalse3falsefalsefalse00falsefalsefalse4truefalsefalse10000001USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 false2Gain (loss) recognized in income on derivative7false 5ppl_IncreaseDecreaseInFairValueAndAmortOfHedgedItemInInterestRateFairValueHedgeppl_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse10000001USD$falsefalsefalse3falsefalsefalse00falsefalsefalse4truefalsefalse20000002USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of unrealized gain (loss) and/or amortization of closed-out hedges included in earnings for the period related to a fair value hedged item.No definition available.false2Gain (loss) recognized in income on related item8false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_CashFlowHedgingMemberhttp://www.sec.gov/CIK0000922224duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseCash Flow Hedges [Member]us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashFlowHedgingMemberus-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cash Flow Hedges [Member]9true 4ppl_AmountsIncludedInIncomeStatementOrOtherComprehensiveIncomeAbstractppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]10false 5us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNetus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse5800000058USD$falsefalsefalse2truefalsefalse224000000224USD$falsefalsefalse3truefalsefalse173000000173USD$falsefalsefalse4truefalsefalse433000000433USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624177-113959 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44C -Subparagraph b -Clause 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Gain (loss) reclassified from AOCI into income on derivative (effective portion)11false 5us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNetus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00  USD$falsefalsefalse2truefalsefalse-4000000-4USD$falsefalsefalse3truefalsefalse10000001USD$falsefalsefalse4truefalsefalse-4000000-4USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1),(2) -URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986 false2Gain (loss) recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)12false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse9false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_CashFlowHedgingMember_us-gaap_OtherComprehensiveIncomeLocationAxis_OtherComprehensiveIncomeMemberhttp://www.sec.gov/CIK0000922224duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseCash Flow Hedges [Member]us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashFlowHedgingMemberus-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisexplicitMemberfalsefalseOther Comprehensive Income [Member]us-gaap_OtherComprehensiveIncomeLocationAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherComprehensiveIncomeMemberus-gaap_OtherComprehensiveIncomeLocationAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cash Flow Hedges [Member] | Other Comprehensive Income [Member]13true 4ppl_AmountsIncludedInIncomeStatementOrOtherComprehensiveIncomeAbstractppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]14false 5us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNetus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse4700000047USD$falsefalsefalse2truefalsefalse-5000000-5USD$falsefalsefalse3truefalsefalse129000000129USD$falsefalsefalse4truefalsefalse123000000123USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Gain (loss) recognized in OCI on derivative (effective portion)15false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse13false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_us-gaap_DerivativeInstrumentRiskAxis_InterestRateSwapMember_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_CashFlowHedgingMember_us-gaap_OtherComprehensiveIncomeLocationAxis_OtherComprehensiveIncomeMemberhttp://www.sec.gov/CIK0000922224duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseCash Flow Hedges [Member]us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashFlowHedgingMemberus-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisexplicitMemberfalsefalseInterest Rate Swaps [Member]us-gaap_DerivativeInstrumentRiskAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestRateSwapMemberus-gaap_DerivativeInstrumentRiskAxisexplicitMemberfalsefalseOther Comprehensive Income [Member]us-gaap_OtherComprehensiveIncomeLocationAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_OtherComprehensiveIncomeMemberus-gaap_OtherComprehensiveIncomeLocationAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Other Comprehensive Income [Member]16true 4ppl_AmountsIncludedInIncomeStatementOrOtherComprehensiveIncomeAbstractppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]17false 5us-gaap_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncomeEffectivePortionNetus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse6800000068USD$falsefalsefalse2truefalsefalse-25000000-25USD$falsefalsefalse3truefalsefalse7700000077USD$falsefalsefalse4truefalsefalse-22000000-22USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Gain (loss) recognized in OCI on derivative (effective portion)18false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse17false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_us-gaap_DerivativeInstrumentRiskAxis_InterestRateSwapMember_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_CashFlowHedgingMember_us-gaap_IncomeStatementLocationAxis_InterestExpenseMemberhttp://www.sec.gov/CIK0000922224duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseCash Flow Hedges [Member]us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashFlowHedgingMemberus-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisexplicitMemberfalsefalseInterest Rate Swaps [Member]us-gaap_DerivativeInstrumentRiskAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestRateSwapMemberus-gaap_DerivativeInstrumentRiskAxisexplicitMemberfalsefalseInterest Expense [Member]us-gaap_IncomeStatementLocationAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestExpenseMemberus-gaap_IncomeStatementLocationAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Interest Expense [Member]19true 4ppl_AmountsIncludedInIncomeStatementOrOtherComprehensiveIncomeAbstractppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]20false 5us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNetus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1truefalsefalse-4000000-4USD$falsefalsefalse2truefalsefalse-5000000-5USD$falsefalsefalse3truefalsefalse-9000000-9USD$falsefalsefalse4truefalsefalse-9000000-9USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Gain (loss) reclassified from AOCI into income on derivative (effective portion)21false 5us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNetus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00  USD$falsefalsefalse2falsefalsefalse00  USD$falsefalsefalse3falsefalsefalse00  USD$falsefalsefalse4falsefalsefalse00  USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 205G -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959 false2Gain (loss) recognized in income on derivative139false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse153false USDtruefalse$FROM_Apr01_2013_TO_Jun30_2013_dei_LegalEntityAxis_KentuckyUtilitiesCoMember_us-gaap_BalanceSheetLocationAxis_RegulatoryLiabilitiesNoncurrentMember_us-gaap_DerivativeInstrumentRiskAxis_InterestRateSwapMember_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_CashFlowHedgingMemberhttp://www.sec.gov/CIK0000922224duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseKentucky Utilities Co [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldippl_KentuckyUtilitiesCoMemberdei_LegalEntityAxisexplicitMemberfalsefalseCash Flow Hedges [Member]us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_CashFlowHedgingMemberus-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxisexplicitMemberfalsefalseInterest Rate Swaps [Member]us-gaap_DerivativeInstrumentRiskAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_InterestRateSwapMemberus-gaap_DerivativeInstrumentRiskAxisexplicitMemberfalsefalseRegulatory Liabilities Noncurrent [Member]us-gaap_BalanceSheetLocationAxisxbrldihttp://xbrl.org/2006/xbrldippl_RegulatoryLiabilitiesNoncurrentMemberus-gaap_BalanceSheetLocationAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Kentucky Utilities Co [Member] | Cash Flow Hedges [Member] | Interest Rate Swaps [Member] | Regulatory Liabilities Noncurrent [Member]140true 4ppl_AmountsIncludedInIncomeStatementOrOtherComprehensiveIncomeAbstractppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Amounts Included in Income, OCI or Regulatory Liabilities/Assets [Abstract]141false 5ppl_DerivativeInstrumentsGainLossRecognizedInRegulatoryLiabilitiesAssetsppl_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2400000024USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse2900000029USD$falsetruefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount of gain (loss) recognized as regulatory assets/liabilities during the period on derivative instruments designated as hedging instruments and not designated as hedging instruments for which regulatory treatment is being applied.No definition available.false2Gain (loss) recognized as regulatory liabilities/assets1Differs from the Statement of Income due to intra-month transactions that PPL defines as spot activity, which is not accounted for as a derivative.2Differs from the Statements of Income due to intra-month transactions that PPL Energy Supply defines as spot activity, which is not accounted for as a derivative.falseDerivative Instruments and Hedging Activities (Gains and Losses) (Details) (USD $)MillionsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://pplweb.com/role/DisclosureDerivativeInstrumentsAndHedgingActivitiesGainsAndLossesDetails4141