v2.4.0.6

Risk Management, Derivative Instruments And Hedging Activities (Notional Amounts Of Derivative Instruments) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 dth GWh | Dec. 31, 2012 GWh dth
Notional Amounts Of Derivative Instruments Related To Interest Rate Risk |  |  |  |
Cash flow hedges | $ 1,047 | [1] | $ 1,047 | [1]
Undesignated contracts | 238 |  | 290 |
Fair value hedges | 250 |  | 250 |
Total Notional Amount | 1,535 |  | 1,587 |
Non-recourse Long-term debt of Variable Interest Entities | 1,255 |  | 852 |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value |  |  |  |
Electricity-energy (Gigawatt-hours) | 56,890 |  | 52,104 |
Natural gas (in decatherms) | 516,000,000 |  | 528,000,000 |
Cash Flow Hedging [Member] |  |  |  |
Notional Amounts Of Derivative Instruments Related To Interest Rate Risk |  |  |  |
Non-recourse Long-term debt of Variable Interest Entities | 620 |  | 620 |
Duke Energy Carolinas [Member] |  |  |  |
Notional Amounts Of Derivative Instruments Related To Interest Rate Risk |  |  |  |
Non-recourse Long-term debt of Variable Interest Entities | 300 |  | 300 |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value |  |  |  |
Electricity-energy (Gigawatt-hours) | 1,802 |  | 2,028 |
Progress Energy [Member] |  |  |  |
Notional Amounts Of Derivative Instruments Related To Interest Rate Risk |  |  |  |
Undesignated contracts |  |  | 50 |
Total Notional Amount |  |  | 50 |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value |  |  |  |
Electricity-energy (Gigawatt-hours) | 1,850 |  | 1,850 |
Natural gas (in decatherms) | 335,000,000 |  | 348,000,000 |
Duke Energy Progress [Member] |  |  |  |
Notional Amounts Of Derivative Instruments Related To Interest Rate Risk |  |  |  |
Undesignated contracts |  |  | 50 |
Total Notional Amount |  |  | 50 |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value |  |  |  |
Electricity-energy (Gigawatt-hours) | 1,850 |  | 1,850 |
Natural gas (in decatherms) | 110,000,000 |  | 118,000,000 |
Duke Energy Florida [Member] |  |  |  |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value |  |  |  |
Natural gas (in decatherms) | 225,000,000 |  | 230,000,000 |
Duke Energy Ohio [Member] |  |  |  |
Notional Amounts Of Derivative Instruments Related To Interest Rate Risk |  |  |  |
Undesignated contracts | 27 |  | 27 |
Fair value hedges | 250 |  | 250 |
Total Notional Amount | 277 |  | 277 |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value |  |  |  |
Electricity-energy (Gigawatt-hours) | 53,173 | [2] | 51,215 | [2]
Natural gas (in decatherms) | 181,000,000 |  | 180,000,000 |
Duke Energy Indiana [Member] |  |  |  |
Notional Amounts Of Derivative Instruments Related To Interest Rate Risk |  |  |  |
Undesignated contracts | 200 |  | 200 |
Total Notional Amount | $ 200 |  | $ 200 |
Underlying Notional Amounts For Derivative Instruments Accounted For At Fair Value |  |  |  |
Electricity-energy (Gigawatt-hours) | 406 |  | 97 |
[1] | Duke Energy includes amounts related to non-recourse variable rate long-term debt of VIEs of $620 million at March 31, 2013, and at December 31, 2012, respectively.
[2] | Amounts at Duke Energy Ohio include intercompany positions that are eliminated at Duke Energy.

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- Definition Sum of the carrying values as of the balance sheet date of all non-recourse long-term debt of variable interest entities, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any. + References No definition available. + Details
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