Organization And Basis Of Presentation (Schedule Of Unbilled Revenues With Restricted Receivables) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended
	Jul. 02, 2012	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Stockholders' Equity Note [Abstract]
Stockholders' equity note, stock split, conversion ratio	0.333
Unbilled Receivables [Abstract]
Unbilled receivables, current		$ 899		$ 920
Income Amounts Attributable to Parent, Disclosures [Abstract]
Income (loss) from continuing operations attributable to parent		634	293
Income (loss) from discontinued operations, net of tax, attributable to parent			2
Net income (loss) attributable to Duke Energy Corporation		634	295
Duke Energy Carolinas [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current		314		315
Progress Energy [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current		193		187
Income Amounts Attributable to Parent, Disclosures [Abstract]
Income (loss) from continuing operations attributable to parent		153	139
Income (loss) from discontinued operations, net of tax, attributable to parent			11
Net income (loss) attributable to Duke Energy Corporation		153	150
Duke Energy Progress [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current		115		112
Duke Energy Florida [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current		78		74
Duke Energy Ohio [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current		49		47
Unbilled revenues sold to CRC		74		90
Duke Energy Indiana [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current		3		3
Unbilled revenues sold to CRC		$ 122		$ 132