v3.3.0.814

Employee Benefit Plans (Employee Savings Plans) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014
Employee Savings Plans [Abstract] |  |  |  |
Employer matching contributions | $ 34 | $ 30 | $ 120 | $ 110
Duke Energy Carolinas [Member] |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |
Employer matching contributions | 11 | 10 | 40 | 36
Progress Energy [Member] |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |
Employer matching contributions | 10 | 10 | 36 | 33
Duke Energy Progress [Member] |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |
Employer matching contributions | 7 | 7 | 26 | 23
Duke Energy Florida [Member] |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |
Employer matching contributions | 3 | 3 | 10 | 10
Duke Energy Ohio [Member] |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |
Employer matching contributions |  |  | 2 | 2
Duke Energy Indiana [Member] |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |
Employer matching contributions | $ 1 | $ 1 | $ 5 | $ 5

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- References No definition available. + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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