v3.3.0.814

Business Segments (Net Loss) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014
Segment Reporting Information [Line Items] |  |  |  |
Segment income | $ 937 | $ 888 | $ 2,310 | $ 2,356
Interest expense | 402 | 405 | 1,208 | 1,212
Duke Energy Carolinas [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Interest expense | 105 | 104 | 313 | 307
Duke Energy Carolinas [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment income | (10) | (19) | (28) | (67)
Progress Energy [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment income |  | 329 |  | 739
Interest expense | 170 | 166 | 504 | 502
Progress Energy [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment income | (3) | (48) | (87) | (145)
Interest expense | 61 | 58 | 180 | 181
Duke Energy Progress [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Interest expense | 59 | 57 | 175 | 172
Duke Energy Progress [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment income | (4) | (10) | (12) | (23)
Duke Energy Florida [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Interest expense | 50 | 51 | 149 | 150
Duke Energy Florida [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment income | (3) | (5) | (9) | (16)
Duke Energy Indiana [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Interest expense | 44 | 40 | 132 | 127
Duke Energy Indiana [Member] | Other [Member] |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Segment income | $ (2) | $ (3) | $ (6) | $ (10)

X
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