v2.4.0.6

Variable Interest Entities (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |  | 3 Months Ended |  | 3 Months Ended
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Mar. 31, 2013 | Dec. 31, 2010 DukeNet And Alinda Capital Partners LLC Ownership In The New Joint Venture [Member] | Mar. 31, 2013 Cinergy Receivables [Member] | Mar. 31, 2013 Cinergy Receivables [Member] Minimum [Member] | Mar. 31, 2013 Cinergy Receivables [Member] Maximum [Member] | Mar. 31, 2013 CinCap V [Member] | Mar. 31, 2013 Duke Energy Carolinas [Member] DERF [Member] Variable Interest Entity, Primary Beneficiary [Member] | Dec. 31, 2012 Progress Energy [Member] FPC Capital I Trust [Member] | Mar. 31, 2013 Duke Energy Ohio [Member] Cinergy Receivables [Member] | Mar. 31, 2013 Duke Energy Ohio [Member] Other VIEs [Member] | Mar. 31, 2013 Duke Energy Indiana [Member] Cinergy Receivables [Member]
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |  |  |
Proceeds received for sale of receivables, portion received as note payable |  |  | 25.00% |  |  |  |  |  |  |  |
Minimum Equity Balance required by Cinergy Receivables |  |  | $ 3 |  |  |  |  |  |  |  |
Subordinated retained interest limitation of the total proceeds |  |  |  | 10.00% | 20.00% |  |  |  |  |  |
Secured credit facility of variable interest entities |  |  |  |  |  |  | 300 |  |  |  |
Fixed rate used when selling receivables |  |  |  |  |  |  |  |  | 1.00% |  | 1.00%
Equity ownership interest rate |  | 50.00% |  |  |  |  |  |  |  |  |
Senior secured credit facility |  | 150 |  |  |  |  |  |  |  |  |
Line of credit facility, expiration date | Nov. 01, 2016 |  | Nov. 01, 2013 |  |  |  | Aug. 01, 2014 |  |  |  |
Ownership interest in OVEC |  |  |  |  |  |  |  |  |  | 9.00% |
CinCap purchased power contract expiration |  |  |  |  |  | 2016 |  |  |  |  |
Debt instrument, face amount |  |  |  |  |  |  |  | $ 300 |  |  |

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- Definition Duke Energy's expiration date for purchased power contract with Central Maine Power Company. + References No definition available. + Details
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- Definition Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 + Details
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