v3.3.0.814

Acquisitions and Dispositions (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Oct. 24, 2015 | Sep. 30, 2015 | Sep. 30, 2015 | Sep. 30, 2014
Significant Acquisitions and Disposals [Abstract] |  |  |  |
Payments to acquire businesses |  |  | $ 1,317 | $ 16
Asset retirement obligations assumed |  |  | 213 |
Piedmont Natural Gas [Member] | Subsequent Event [Member] | Scenario, Forecast [Member] |  |  |  |
Significant Acquisitions and Disposals [Abstract] |  |  |  |
Payments to acquire businesses | $ 4,900 |  |  |
Business Acquisition, Share Price | $ 60 |  |  |
Long-term debt assumed | $ 1,800 |  |  |
Acquirer Termination Fee | 250 |  |  |
Acquiree Termination Fee | 125 |  |  |
Piedmont Natural Gas [Member] | Subsequent Event [Member] | Scenario, Forecast [Member] | Minimum [Member] |  |  |  |
Significant Acquisitions and Disposals [Abstract] |  |  |  |
Proceeds from Issuance or Sale of Equity | 500 |  |  |
Piedmont Natural Gas [Member] | Subsequent Event [Member] | Scenario, Forecast [Member] | Maximum [Member] |  |  |  |
Significant Acquisitions and Disposals [Abstract] |  |  |  |
Proceeds from Issuance or Sale of Equity | $ 750 |  |  |
Duke Energy Progress [Member] |  |  |  |
Significant Acquisitions and Disposals [Abstract] |  |  |  |
Payments to acquire businesses |  |  | 1,249 |
Asset retirement obligations assumed |  |  | 204 |
Duke Energy Progress [Member] | NCEMPA Generating Assets [Member] |  |  |  |
Significant Acquisitions and Disposals [Abstract] |  |  |  |
Payments to acquire businesses |  | $ 1,250 |  |
Purchase acquisition adjustment |  | 350 | 350 |
Nuclear decommissioning trust fund assets transferred |  | 287 | 287 |
Asset retirement obligations assumed |  | 204 |  |
Impact on revenue from acquisition |  | 40 | 40 |
Impact on net income from acquisition |  | 7 | 7 |
Duke Energy Ohio [Member] | Midwest Generation Business [Member] |  |  |  |
Discontinued Operations and Disposal Groups [Abstract] |  |  |  |
Disposal Group, Including Discontinued Operation, Consideration |  | $ 2,800 | $ 2,800 |

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