v2.4.0.8

Derivatives and Hedging (Notional Amounts of Derivative Instruments) (Details) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2014 GWh dth | Dec. 31, 2013 GWh dth
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value [Abstract] |  |  |  |
Electricity-energy (Gigawatt-hours) | 29,569 | [1] | 71,466 | [1]
Natural gas (millions of decatherms) | 659,000,000 |  | 636,000,000 |
Duke Energy Carolinas [Member] |  |  |  |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value [Abstract] |  |  |  |
Electricity-energy (Gigawatt-hours) |  | [1] | 1,205 | [1]
Natural gas (millions of decatherms) |  |  |  |
Progress Energy [Member] |  |  |  |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value [Abstract] |  |  |  |
Electricity-energy (Gigawatt-hours) |  | [1] | 925 | [1]
Natural gas (millions of decatherms) | 319,000,000 |  | 363,000,000 |
Duke Energy Progress [Member] |  |  |  |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value [Abstract] |  |  |  |
Electricity-energy (Gigawatt-hours) |  | [1] | 925 | [1]
Natural gas (millions of decatherms) | 117,000,000 |  | 141,000,000 |
Duke Energy Florida [Member] |  |  |  |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value [Abstract] |  |  |  |
Electricity-energy (Gigawatt-hours) |  | [1] |  | [1]
Natural gas (millions of decatherms) | 202,000,000 |  | 222,000,000 |
Duke Energy Ohio [Member] |  |  |  |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value [Abstract] |  |  |  |
Electricity-energy (Gigawatt-hours) | 25,680 | [1] | 69,362 | [1]
Natural gas (millions of decatherms) | 340,000,000 |  | 274,000,000 |
Duke Energy Indiana [Member] |  |  |  |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value [Abstract] |  |  |  |
Electricity-energy (Gigawatt-hours) | 607 | [1] | 203 | [1]
Natural gas (millions of decatherms) |  |  |  |
[1] | Amounts at Duke Energy Ohio include intercompany positions that eliminate at Duke Energy.

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- Definition Electricity energy gigawatt hours + References No definition available. + Details
Name: | duk_ElectricityEnergyGigawattHours
Namespace Prefix: | duk_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

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- Definition Aggregate notional amount of natural gas of derivatives not designated as a hedging instrument. + References No definition available. + Details
Name: | duk_NaturalGasDecatherms
Namespace Prefix: | duk_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | duration

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- Details
Name: | duk_NotionalAmountOfDerivativesAtFairValueAbstract
Namespace Prefix: | duk_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration