Regulatory Matters (Schedule of Net Carrying Value Of Facilities As Well As the Remaining Non-current Regulatory Assets) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015 MW	Dec. 31, 2014
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	1,704
Remaining net book value (in millions)	$ 70,301	$ 70,046
Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	243
Duke Energy Carolinas [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	24,747	24,672
Duke Energy Carolinas [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	110
Progress Energy [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	873
Remaining net book value (in millions)	25,353	25,144
Progress Energy [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	120
Duke Energy Progress [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	15,282	15,186
Duke Energy Progress [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	150
Duke Energy Florida [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	873
Remaining net book value (in millions)	10,068	9,955
Duke Energy Florida [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	120
Duke Energy Ohio [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	163
Remaining net book value (in millions)	4,953	4,937
Duke Energy Ohio [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	9
Duke Energy Indiana [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	668
Remaining net book value (in millions)	8,866	8,815
Duke Energy Indiana [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	$ 114