XML 123 R83.htm IDEA: XBRL DOCUMENT
v3.20.2

Fair Value Measurements (Quantitative Level 3 Fair Value Disclosures) (Details) $ in Millions | Sep. 30, 2020 USD ($) $ / MWh $ / MMBTU | Jun. 30, 2020 USD ($) | Dec. 31, 2019 USD ($) $ / MWh $ / MMBTU | Sep. 30, 2019 USD ($) | Jun. 30, 2019 USD ($) | Dec. 31, 2018 USD ($)
--- | --- | --- | --- | --- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Net derivative asset (liability) | $ | $ (203) | $ (92) | $ (102) | $ (90) | $ (79) | $ (113)
Electricity contracts | RTO auction pricing |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Net derivative asset (liability) | $ | $ (102) |  |  |  |  |
Electricity contracts | RTO auction pricing | Minimum |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | 14.92 |  |  |  |  |
Electricity contracts | RTO auction pricing | Maximum |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | 151.18 |  |  |  |  |
Electricity contracts | RTO auction pricing | Weighted Average |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | 29.63 |  |  |  |  |
Duke Energy Ohio | FTRs | RTO auction pricing |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Net derivative asset (liability) | $ | $ 2 |  | $ 4 |  |  |
Duke Energy Ohio | FTRs | RTO auction pricing | Minimum |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | 0 |  | 0.59 |  |  |
Duke Energy Ohio | FTRs | RTO auction pricing | Maximum |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | 1.90 |  | 3.47 |  |  |
Duke Energy Ohio | FTRs | RTO auction pricing | Weighted Average |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | 0.64 |  | 2.07 |  |  |
Duke Energy Indiana |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Net derivative asset (liability) | $ | $ 8 | 10 | $ 11 | 16 | 28 | 22
Duke Energy Indiana | FTRs | RTO auction pricing |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Net derivative asset (liability) | $ | $ 8 |  | $ 11 |  |  |
Duke Energy Indiana | FTRs | RTO auction pricing | Minimum |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | (1.03) |  | (0.66) |  |  |
Duke Energy Indiana | FTRs | RTO auction pricing | Maximum |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | 6.10 |  | 9.24 |  |  |
Duke Energy Indiana | FTRs | RTO auction pricing | Weighted Average |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | 0.74 |  | 1.15 |  |  |
Piedmont Natural Gas |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Net derivative asset (liability) | $ | $ (111) | $ (105) | $ (117) | $ (111) | $ (114) | $ (141)
Piedmont Natural Gas | Electricity and natural gas contracts | Discounted cash flow |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Net derivative asset (liability) | $ | $ (111) |  | $ (117) |  |  |
Piedmont Natural Gas | Electricity and natural gas contracts | Discounted cash flow | Minimum |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | $ / MMBTU | 1.81 |  | 1.59 |  |  |
Piedmont Natural Gas | Electricity and natural gas contracts | Discounted cash flow | Maximum |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | $ / MMBTU | 2.50 |  | 2.46 |  |  |
Piedmont Natural Gas | Electricity and natural gas contracts | Discounted cash flow | Weighted Average |  |  |  |  |  |
Fair Value Measurement Inputs and Valuation Techniques |  |  |  |  |  |
Input measurements (in usd per MWh and usd per MMBtu) | $ / MMBTU | 2.11 |  | 1.91 |  |  |

X
- Definition Value of input used to measure net derivative asset (liability). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_DerivativeAssetLiabilityNetMeasurementInput
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19279-110258 + Details
Name: | us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=duk_DerivativeFinancialInstrumentsLiabilitiesCommodityPowerContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_MarketApproachValuationTechniqueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_DukeEnergyOhioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=duk_DerivativeFinancialInstrumentsLiabilitiesFinancialTransmissionRightsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_DukeEnergyIndianaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=duk_PiedmontNaturalGasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByLiabilityClassAxis=us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_ValuationTechniqueDiscountedCashFlowMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |