v2.4.0.8

Employee Benefit Plans (Employee Savings Plans) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013
Employee Savings Plans [Abstract] |  |  |  |  |  |
Pretax employer matching contributions | $ 30 | [1] | $ 30 | $ 110 | [1] | $ 101
Duke Energy Carolinas [Member] |  |  |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |  |  |
Pretax employer matching contributions | 10 | [1] | 10 | 36 | [1] | 34
Progress Energy [Member] |  |  |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |  |  |
Pretax employer matching contributions | 10 | [1] | 12 | 33 | [1] | 34
Duke Energy Progress [Member] |  |  |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |  |  |
Pretax employer matching contributions | 7 | [1] | 7 | 23 | [1] | 19
Duke Energy Florida [Member] |  |  |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |  |  |
Pretax employer matching contributions | 3 | [1] | 4 | 10 | [1] | 11
Duke Energy Ohio [Member] |  |  |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |  |  |
Pretax employer matching contributions |  | [1] |  | 2 | [1] | 2
Duke Energy Indiana [Member] |  |  |  |  |  |
Employee Savings Plans [Abstract] |  |  |  |  |  |
Pretax employer matching contributions | $ 1 | [1] | $ 2 | $ 5 | [1] | $ 5
[1] | For the three and nine months ended September 30, 2014, amounts include the additional contribution of 4 percent of eligible pay per pay period for employees not eligible to participate in a defined benefit plan.

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- 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=6414718&loc=d3e28014-114942 + Details
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