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5ppl_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetAndLiabilityTransfersOutppl_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00  USD$falsefalsefalse2falsefalsefalse00  USD$falsefalsefalse3truefalsefalse-4000000-4USD$falsefalsefalse4truefalsefalse-3000000-3USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents transfers out of net assets (liabilities) measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.No definition available.false2Transfers out of Level 343false 5ppl_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetAndLiabilityValueppl_falsedebitinstantfalsefalsefalsefalsefalsefalsetruefalseperiodEndLabel1truefalsefalse30000003USD$falsefalsefalse2truefalsefalse1000000010USD$falsefalsefalse3truefalsefalse30000003USD$falsefalsefalse4truefalsefalse1000000010USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the beginning and ending balances of net assets (liabilities) measured at fair value using significant unobservable inputs (Level 3) in a rollforward of the activity between periods.No definition available.false2Balance at end of period44false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse17false 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period47true 5ppl_TotalRealizedUnrealizedGainsLossesAbstractppl_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Total realized/unrealized gains (losses)48false 6us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarningsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1400000014USD$falsefalsefalse2truefalsefalse-2000000-2USD$falsefalsefalse3truefalsefalse60000006USD$falsefalsefalse4truefalsefalse1600000016USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false2Included in earnings49false 6us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisGainLossIncludedInOtherComprehensiveIncomeLossus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00  USD$falsefalsefalse2truefalsefalse-2000000-2[1]USD$falsefalsefalse3falsefalsefalse00  USD$falsefalsefalse4falsefalsefalse00  USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of gain (loss) recognized in other comprehensive income, arising from assets, liabilities and financial instruments classified in shareholders' equity measured at fair value on a recurring basis using unobservable inputs (level 3).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false2Included in OCI50false 5ppl_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetLiabilitySalesppl_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-2000000-2USD$falsefalsefalse2truefalsefalse-3000000-3USD$falsefalsefalse3truefalsefalse-2000000-2USD$falsefalsefalse4truefalsefalse-3000000-3USD$falsefalsefalsexbrli:monetaryItemTypemonetarySales that have taken place during the period in relation to net assets and liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.No definition available.false2Sales51false 5ppl_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetLiabilitySettlementsppl_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse40000004USD$falsefalsefalse2truefalsefalse-5000000-5USD$falsefalsefalse3truefalsefalse30000003USD$falsefalsefalse4truefalsefalse-11000000-11USD$falsefalsefalsexbrli:monetaryItemTypemonetarySettlements that have taken place during the period in relation to net assets and liabilities measured at fair value and categorized within Level 3 of the fair value hierarchy.No definition available.false2Settlements52false 5ppl_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetAndLiabilityTransfersInppl_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse90000009USD$falsefalsefalse2truefalsefalse1400000014USD$falsefalsefalse3truefalsefalse1000000010USD$falsefalsefalse4truefalsefalse1400000014USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents transfers into net assets (liabilities) measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.No definition available.false2Transfers into Level 353false 5ppl_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetAndLiabilityTransfersOutppl_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse40000004USD$falsefalsefalse2truefalsefalse60000006USD$falsefalsefalse3truefalsefalse40000004USD$falsefalsefalse4truefalsefalse-2000000-2USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents transfers out of net assets (liabilities) measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period.No definition available.false2Transfers out of Level 354false 5ppl_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetAndLiabilityValueppl_falsedebitinstantfalsefalsefalsefalsefalsefalsetruefalseperiodEndLabel1truefalsefalse5600000056USD$falsefalsefalse2truefalsefalse4600000046USD$falsefalsefalse3truefalsefalse5600000056USD$falsefalsefalse4truefalsefalse4600000046USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the beginning and ending balances of net assets (liabilities) measured at fair value using significant unobservable inputs (Level 3) in a rollforward of the activity between periods.No definition available.false2Balance at end of period55false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse21false 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6us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisGainLossIncludedInEarningsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1400000014USD$falsefalsefalse2truefalsefalse-2000000-2USD$falsefalsefalse3truefalsefalse60000006USD$falsefalsefalse4truefalsefalse1600000016USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false2Included in earnings60false 6us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisGainLossIncludedInOtherComprehensiveIncomeLossus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00  USD$falsefalsefalse2truefalsefalse-1000000-1[1]USD$falsefalsefalse3falsefalsefalse00  USD$falsefalsefalse4truefalsefalse10000001[1]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of gain (loss) recognized in other comprehensive income, arising from assets, liabilities and financial instruments classified in shareholders' equity measured at fair value on a recurring basis using unobservable inputs (level 3).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 false2Included in OCI61false 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5ppl_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisNetAssetAndLiabilityValueppl_falsedebitinstantfalsefalsefalsefalsefalsefalsetruefalseperiodEndLabel1truefalsefalse4000000040USD$falsefalsefalse2truefalsefalse3400000034USD$falsefalsefalse3truefalsefalse4000000040USD$falsefalsefalse4truefalsefalse3400000034USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis element represents the beginning and ending balances of net assets (liabilities) measured at fair value using significant unobservable inputs (Level 3) in a rollforward of the activity between periods.No definition available.false2Balance at end of period66false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse25false 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