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	9 Months Ended
	Sep. 30, 2014 MW		Dec. 31, 2013
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	2,297
Remaining net book value (in millions)	$ 69,595		$ 69,490
Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	256	[1]
Duke Energy Carolinas [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	200	[2]
Remaining net book value (in millions)	25,126		23,012
Duke Energy Carolinas [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	19	[1],[2]
Progress Energy [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	873
Remaining net book value (in millions)	24,399		23,382
Progress Energy [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	109	[1]
Duke Energy Florida [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	873	[3]
Remaining net book value (in millions)	9,815		9,611
Duke Energy Florida [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	109	[1],[3]
Duke Energy Ohio [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	556	[4]
Remaining net book value (in millions)	4,905		8,235
Duke Energy Ohio [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	9	[1],[4]
Duke Energy Indiana [Member]
Public Utilities, General Disclosures [Line Items]
Capacity (in MW)	668	[5]
Remaining net book value (in millions)	8,780		8,576
Duke Energy Indiana [Member] | Generation Facilities To Be Retired [Member]
Public Utilities, General Disclosures [Line Items]
Remaining net book value (in millions)	$ 119	[1],[5]

[1] Included in Property, plant and equipment, net as of September 30, 2014, on the Condensed Consolidated Balance Sheets.

[2] Includes Lee Units 1 and 2. Excludes 170 MW Lee Unit 3 that is expected to be converted to gas in 2014. Duke Energy Carolinas expects to retire or convert these units by December 2020 in conjunction with a settlement agreement associated with the Cliffside Unit 6 air permit.

[3] Includes Crystal River Units 1 and 2.

[4] Includes Beckjord Units 5 and 6 and Miami Fort Unit 6. Beckjord units have no remaining book value and were retired October 1, 2014.

[5] Includes Wabash River Units 2 through 6. Wabash River Unit 6 is being evaluated for potential conversion to gas. Duke Energy Indiana committed to retire or convert these units by June 2018 in conjunction with a settlement agreement associated with the Edwardsport air permit.