v2.4.0.8

Commitments and Contingencies (Schedule of Reserves) (Details) (USD $) In Millions, unless otherwise specified | Sep. 30, 2014 | Dec. 31, 2013
--- | --- | ---
Loss Contingencies [Line Items] |  |
Reserves for legal matters | $ 227 | $ 204
Progress Energy [Member] |  |
Loss Contingencies [Line Items] |  |
Reserves for legal matters | 70 | 78
Duke Energy Progress [Member] |  |
Loss Contingencies [Line Items] |  |
Reserves for legal matters | 9 | 10
Duke Energy Florida [Member] |  |
Loss Contingencies [Line Items] |  |
Reserves for legal matters | $ 41 | $ 43

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- Definition Amount of loss contingency liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 + Details
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