Duke Energy's expiration date for purchased power contract with Central Maine Power Company.

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Duke Energy's ownership interest in OVEC.

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Proceeds Received For Sale Of Receivables Portion Received As Note Payable

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Minimum equity Balance required by Cinergy Receivables

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Sale of Receivables, Fixed Rate Used in Calculation

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Secured Credit Facility Of Vie

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Subordinated Retained Interest Limitation Of The Total Proceeds

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Date the credit facility terminates, in CCYY-MM-DD format.

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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.

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Variable Interest Entities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		3 Months Ended						3 Months Ended
	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