Regulatory Matters (Schedule of Net Carrying Value Of Facilities and Megawatt Capacity) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2016 USD ($) MW	Dec. 31, 2015 USD ($)
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	$ 77,329	$ 75,709
Generation Facilities To Be Retired Net	$ 598	548
Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	1,471
Remaining net book value (in millions)	$ 295
Duke Energy Carolinas [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	26,405	25,877
Progress Energy [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	29,139	28,347
Generation Facilities To Be Retired Net	$ 506	548
Progress Energy [Member] | Generation Facilities To Be Retired [Member] | Crystal River Units 1 and 2 [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	873
Remaining net book value (in millions)	$ 126
Duke Energy Progress [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	17,927	17,720
Generation Facilities To Be Retired Net	506	548
Duke Energy Florida [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	$ 11,208	10,623
Duke Energy Florida [Member] | Generation Facilities To Be Retired [Member] | Crystal River Units 1 and 2 [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	873
Remaining net book value (in millions)	$ 126
Duke Energy Ohio [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	5,370	5,243
Duke Energy Indiana [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	9,551	$ 9,523
Generation Facilities To Be Retired Net	93
Duke Energy Indiana [Member] | Wabash River Unit 6 [Member]
Public Utilities, General Disclosures [Line Items]
Generation Facilities To Be Retired Net	$ 93
Duke Energy Indiana [Member] | Generation Facilities To Be Retired [Member] | Wabash River Unit 6 [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	318
Remaining net book value (in millions)	$ 34
Duke Energy Indiana [Member] | Generation Facilities To Be Retired [Member] | Gallagher Units 2 and 4 [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW) | MW	280
Remaining net book value (in millions)	$ 135