v3.3.0.814

Derivatives and Hedging (Notional Amounts of Derivative Instruments) (Details) Bcf in Millions, $ in Millions | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2015 USD ($) GWh Bcf | Dec. 31, 2014 USD ($) GWh Bcf | Oct. 31, 2015 USD ($)
Commodity Contracts [Member] | Electricity [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, energy measure, in gigawatt-hours | GWh | 76 | 25,370 |
Commodity Contracts [Member] | Natural Gas [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, volume, in millions of decatherms | Bcf | 389 | 676 |
Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 1,241 | $ 1,027 |
Duke Energy Carolinas [Member] | Commodity Contracts [Member] | Natural Gas [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, volume, in millions of decatherms | Bcf | 61 | 35 |
Progress Energy [Member] | Commodity Contracts [Member] | Natural Gas [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, volume, in millions of decatherms | Bcf | 328 | 328 |
Progress Energy [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 500 | $ 250 |
Duke Energy Progress [Member] | Commodity Contracts [Member] | Natural Gas [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, volume, in millions of decatherms | Bcf | 110 | 116 |
Duke Energy Progress [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 250 |  |
Duke Energy Florida [Member] | Commodity Contracts [Member] | Natural Gas [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, volume, in millions of decatherms | Bcf | 218 | 212 |
Duke Energy Florida [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 250 | $ 250 |
Duke Energy Ohio [Member] | Commodity Contracts [Member] | Electricity [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, energy measure, in gigawatt-hours | GWh | 3 | 19,141 |
Duke Energy Ohio [Member] | Commodity Contracts [Member] | Natural Gas [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, volume, in millions of decatherms | Bcf |  | 313 |
Duke Energy Ohio [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 27 | $ 27 |
Duke Energy Indiana [Member] | Commodity Contracts [Member] | Electricity [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount, energy measure, in gigawatt-hours | GWh | 39 |  |
Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 714 | 750 |
Not Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | 527 | 277 |
Not Designated as Hedging Instrument [Member] | Progress Energy [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | 500 | 250 |
Not Designated as Hedging Instrument [Member] | Duke Energy Progress [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 250 |  |
Floating interest rate | 1.75% |  |
Not Designated as Hedging Instrument [Member] | Duke Energy Florida [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 250 | 250 |
Not Designated as Hedging Instrument [Member] | Duke Energy Ohio [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | 27 | 27 |
Variable Interest Entity, Primary Beneficiary [Member] | Designated as Hedging Instrument [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | $ 509 | $ 541 |
Subsequent Event [Member] | Duke Energy Carolinas [Member] | Interest Rate Contracts [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount |  |  | $ 400

X
- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- 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
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