Debt and Credit Facilities (Summary of Debt Issuances) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Apr. 30, 2014
Debt Instrument [Line Items]
Debt issuances	$ 2,922,000,000	$ 4,023,000,000
April 2014 3.75% Senior Unsecured Notes Maturing April 2024 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Apr. 01, 2014
Debt maturity date	Apr. 30, 2024
Debt issuances	600,000,000
Interest rate	3.75%
Repayments of Debt	402,000,000
April 2014 0.613% Senior Unsecured Floating Notes Maturing April 2017 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Apr. 01, 2014
Debt maturity date	Apr. 30, 2017
Debt issuances	400,000,000
Interest rate	0.613%
Fixed credit spread	0.38%
Repayments of Debt	402,000,000
June 2014 11.970% Senior Unsecured Floating Notes Maturing May 2019 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Jun. 01, 2014
Debt maturity date	May 31, 2019
Debt issuances	108,000,000
Interest rate	11.97%
Repayments of Debt	196,000,000
June 2014 13.680% Senior Unsecured Floating Notes Maturing May 2021 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Jun. 01, 2014
Debt maturity date	May 31, 2021
Debt issuances	110,000,000
Interest rate	13.68%
Repayments of Debt	196,000,000
March 2014 0.863% Secured Credit Facility Maturing March 2017 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Mar. 01, 2014
Debt maturity date	Mar. 31, 2017
Debt issuances	225,000,000
Interest rate	0.863%
July 2014 5.340% Secured Debt Maturing July 2036 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Jul. 01, 2014
Debt maturity date	Jul. 31, 2036
Debt issuances	129,000,000
Interest rate	5.34%
March 2014 4.375% First Mortgage Bonds Maturing March 2044 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date	Mar. 01, 2014
Debt maturity date	Mar. 31, 2044
Debt issuances	400,000,000
Interest rate	4.375%
March 2014 0.435% First Mortgage Bonds Maturing March 2017[Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date	Mar. 01, 2014
Debt maturity date	Mar. 31, 2017
Debt issuances	250,000,000
Interest rate	0.435%
Fixed credit spread	0.20%
November 2014 4.150% Fixed First Mortgage Bonds Maturing December 2044 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date	Nov. 01, 2014
Debt maturity date	Dec. 31, 2044
Debt issuances	500,000,000
Interest rate	4.15%
Repayments of Debt	450,000,000
November 2014 0.432% Floating First Mortgage Bonds Maturing November 2017 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date	Nov. 01, 2014
Debt maturity date	Nov. 30, 2017
Debt issuances	200,000,000
Interest rate	0.432%
Fixed credit spread	0.20%
Repayments of Debt	450,000,000
January 2013 5.125% Junior Subordinated Debentures Maturing January 2073 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Jan. 31, 2013
Debt maturity date		Jan. 31, 2073
Debt issuances		500,000,000
Interest rate		5.125%
Debt instrument, call date, earliest		Jan. 31, 2018
June 2013 2.100% Senior Notes Maturing June 2018 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Jun. 30, 2013
Debt maturity date		Jun. 30, 2018
Debt issuances		500,000,000
Interest rate		2.10%
Repayments of Debt		250,000,000
August 2013 11.000% Non Convertible Debentures Maturing August 2018 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Aug. 31, 2013
Debt maturity date		Aug. 30, 2023
Debt maturity date, start		Aug. 31, 2018
Debt issuances		220,000,000
Interest rate		11.00%
Repayments of Debt		200,000,000
October 2013 3.950% Senior Notes Maturing October 2023 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Oct. 31, 2013
Debt maturity date		Oct. 31, 2023
Debt issuances		400,000,000
Interest rate		3.95%
February 2013 2.043% Term Loans Maturing December 2030 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Feb. 28, 2013
Debt maturity date		Dec. 31, 2030
Debt issuances		203,000,000
Interest rate		2.043%
Percentage of debt hedged by interest rate derivatives		95.00%
February 2013 4.740% Term Loans Maturing June 2037 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Feb. 28, 2013
Debt maturity date		Jun. 30, 2037
Debt issuances		220,000,000
Interest rate		4.74%
April 2013 5.456% Non Recourse Secured Credit Facility Maturing April 2026 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Apr. 30, 2013
Debt maturity date		Apr. 30, 2026
Debt issuances		230,000,000
Interest rate		5.456%
Percentage of debt hedged by interest rate derivatives		75.00%
Incremental debt proceeds		40,000,000
April 2013 5.456% Non Recourse Secured Credit Facility Maturing April 2026 [Member] | Bridge Loan [Member]
Debt Instrument [Line Items]
Repayments of Debt		190,000,000
December 2013 0.852% Secured ARS Maturing December 2016 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Dec. 20, 2013
Debt maturity date		Dec. 20, 2016
Debt issuances		300,000,000
Interest rate		0.852%
March 2013 4.100% First Mortgage Bonds Maturing March 2043 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Mar. 31, 2013
Debt maturity date		Mar. 31, 2043
Debt issuances		500,000,000
Interest rate		4.10%
July 2013 4.900% First Mortgage Bonds Maturing July 2043 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Jul. 31, 2013
Debt maturity date		Jul. 31, 2043
Debt issuances		350,000,000
Interest rate		4.90%
Repayments of Debt		400,000,000
July 2013 0.619% First Mortgage Bonds Maturing July 2016 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Jul. 31, 2013
Debt maturity date		Jul. 31, 2016
Debt issuances		150,000,000
Interest rate		0.619%
Fixed credit spread		0.35%
September 2013 3.800% First Mortgage Bonds Maturing September 2023 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Sep. 30, 2013
Debt maturity date		Sep. 30, 2023
Debt issuances		300,000,000
Interest rate		3.80%
Repayments of Debt		250,000,000
September 2013 0.400% First Mortgage Bonds Maturing March 2015 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Sep. 30, 2013
Debt maturity date		Mar. 31, 2015
Debt issuances		150,000,000
Interest rate		0.40%
Fixed credit spread		0.14%
Parent Company [Member]
Debt Instrument [Line Items]
Debt issuances	1,000,000,000	1,400,000,000
Parent Company [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances			1,000,000,000
Parent Company [Member] | April 2014 3.75% Senior Unsecured Notes Maturing April 2024 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Apr. 01, 2014
Debt maturity date	Apr. 30, 2024
Debt issuances	600,000,000
Interest rate	3.75%
Repayments of Debt	402,000,000
Parent Company [Member] | April 2014 0.613% Senior Unsecured Floating Notes Maturing April 2017 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Apr. 01, 2014
Debt maturity date	Apr. 30, 2017
Debt issuances	400,000,000
Fixed credit spread	0.38%
Repayments of Debt	402,000,000
Parent Company [Member] | January 2013 5.125% Junior Subordinated Debentures Maturing January 2073 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Jan. 31, 2013
Debt maturity date		Jan. 31, 2073
Debt issuances		500,000,000
Interest rate		5.125%
Parent Company [Member] | June 2013 2.100% Senior Notes Maturing June 2018 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Jun. 30, 2013
Debt maturity date		Jun. 30, 2018
Debt issuances		500,000,000
Interest rate		2.10%
Repayments of Debt		250,000,000
Parent Company [Member] | October 2013 3.950% Senior Notes Maturing October 2023 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Oct. 31, 2013
Debt maturity date		Oct. 31, 2023
Debt issuances		400,000,000
Interest rate		3.95%
Progress Energy [Member] | January 2013 5.125% Junior Subordinated Debentures Maturing January 2073 [Member] | Corporate Debt Securities [Member]
Debt Instrument [Line Items]
Interest rate		7.10%
Repayments of Debt		300,000,000
Duke Energy Progress [Member]
Debt Instrument [Line Items]
Debt issuances	1,350,000,000	800,000,000
Duke Energy Progress [Member] | March 2014 4.375% First Mortgage Bonds Maturing March 2044 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date	Mar. 01, 2014
Debt maturity date	Mar. 31, 2044
Debt issuances	400,000,000
Duke Energy Progress [Member] | March 2014 0.435% First Mortgage Bonds Maturing March 2017[Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date	Mar. 01, 2014
Debt maturity date	Mar. 31, 2017
Debt issuances	250,000,000
Fixed credit spread	0.20%
Duke Energy Progress [Member] | November 2014 4.150% Fixed First Mortgage Bonds Maturing December 2044 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date	Nov. 01, 2014
Debt maturity date	Dec. 31, 2044
Debt issuances	500,000,000
Repayments of Debt	450,000,000
Duke Energy Progress [Member] | November 2014 0.432% Floating First Mortgage Bonds Maturing November 2017 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date	Nov. 01, 2014
Debt maturity date	Nov. 30, 2017
Debt issuances	200,000,000
Fixed credit spread	0.20%
Repayments of Debt	450,000,000
Duke Energy Progress [Member] | December 2013 0.852% Secured ARS Maturing December 2016 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date		Dec. 20, 2013
Debt maturity date		Dec. 31, 2016
Debt issuances		300,000,000
Interest rate		0.852%
Duke Energy Progress [Member] | March 2013 4.100% First Mortgage Bonds Maturing March 2043 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Mar. 31, 2013
Debt maturity date		Mar. 31, 2043
Debt issuances		500,000,000
Interest rate		4.10%
Duke Energy Florida [Member]
Debt Instrument [Line Items]
Debt issuances	225,000,000
Duke Energy Florida [Member] | March 2014 0.863% Secured Credit Facility Maturing March 2017 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuance date	Mar. 01, 2014
Debt maturity date	Mar. 31, 2017
Debt issuances	225,000,000
Duke Energy Ohio [Member]
Debt Instrument [Line Items]
Debt issuances		450,000,000
Duke Energy Ohio [Member] | September 2013 3.800% First Mortgage Bonds Maturing September 2023 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Sep. 30, 2013
Debt maturity date		Sep. 30, 2023
Debt issuances		300,000,000
Interest rate		3.80%
Repayments of Debt		250,000,000
Duke Energy Ohio [Member] | September 2013 0.400% First Mortgage Bonds Maturing March 2015 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Sep. 30, 2013
Debt maturity date		Mar. 31, 2015
Debt issuances		150,000,000
Interest rate		0.40%
Fixed credit spread		0.14%
Duke Energy Indiana [Member]
Debt Instrument [Line Items]
Debt issuances		500,000,000
Duke Energy Indiana [Member] | July 2013 4.900% First Mortgage Bonds Maturing July 2043 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Jul. 31, 2013
Debt maturity date		Jul. 31, 2043
Debt issuances		350,000,000
Interest rate		4.90%
Repayments of Debt		400,000,000
Duke Energy Indiana [Member] | July 2013 0.619% First Mortgage Bonds Maturing July 2016 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuance date		Jul. 31, 2013
Debt maturity date		Jul. 31, 2016
Debt issuances		$ 150,000,000
Interest rate		0.619%
Fixed credit spread		0.35%