v3.3.0.814

Organization and Basis of Presentation (Schedule of Unbilled Revenues with Restricted Receivables) (Details) - USD ($) $ in Millions | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | $ 748 | $ 827
Duke Energy Carolinas [Member] |  |
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | 247 | 295
Progress Energy [Member] |  |
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | 220 | 217
Duke Energy Progress [Member] |  |
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | 123 | 135
Duke Energy Florida [Member] |  |
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | 97 | 82
Duke Energy Ohio [Member] |  |
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | 6 |
Duke Energy Indiana [Member] |  |
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | 25 | 27
Cinergy Receivables [Member] | Duke Energy Ohio [Member] |  |
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | 64 | 79
Cinergy Receivables [Member] | Duke Energy Indiana [Member] |  |
Organization And Basis Of Presentation [Line Items] |  |
Unbilled receivables | $ 93 | $ 112

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