Variable Interest Entities (Receivables Sold)(Details) (Cinergy Receivables [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Duke Energy Ohio [Member]
Variable Interest Entities [Line Items]
Receivables sold	$ 321	$ 290
Less: retained interests	127	114
Net receivables sold	194	176
Duke Energy Indiana [Member]
Variable Interest Entities [Line Items]
Receivables sold	319	340
Less: retained interests	134	143
Net receivables sold	$ 185	$ 197

This includes the recognized portion of the total principal amount of financial assets which have been either securitized, used in an asset-backed financing arrangement, or similar transfer which are accounted for as sales and in which the transferor has continuing involvement with the assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

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- Definition

This includes only the derecognized portion of the total principal amount of financial assets which have been either securitized, used in an asset-backed financing arrangement, or similar transfers which are accounted for as sales and in which the transferor has continuing involvement with the assets underlying the transaction (including, but not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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- Definition

The total principal outstanding of financial assets transferred in a securitization, asset-backed financing arrangement, or similar transfer that has been accounted for as sales and in which the transferor continues to have involvement, including both the derecognized and recognized portion of such transferred assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107314-111719

+ Details

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