Organization and Basis of Presentation (Schedule of Unbilled Revenues with Restricted Receivables) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Unbilled Receivables [Abstract]
Unbilled receivables, current	$ 920		$ 920		$ 920
Income Amounts Attributable to Parent, Disclosures [Abstract]
Income (loss) from continuing operations attributable to parent	342	445	976	738
Income (loss) from discontinued operations, net of tax, attributable to parent	(3)	(1)	(3)	1
Net income (loss) attributable to Duke Energy Corporation	339	444	973	739
Duke Energy Carolinas [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current	307		307		315
Progress Energy [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current	217		217		187
Income Amounts Attributable to Parent, Disclosures [Abstract]
Income (loss) from continuing operations attributable to parent	(13)	67	140	206
Income (loss) from discontinued operations, net of tax, attributable to parent	(4)	(4)	(4)	7
Net income (loss) attributable to Duke Energy Corporation	(17)	63	136	213
Duke Energy Progress [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current	122		122		112
Duke Energy Florida [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current	95		95		74
Duke Energy Ohio [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current	50		50		47
Duke Energy Ohio [Member] | CRC [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current	71		71		90
Duke Energy Indiana [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current	13		13		3
Duke Energy Indiana [Member] | CRC [Member]
Unbilled Receivables [Abstract]
Unbilled receivables, current	$ 117		$ 117		$ 132