Debt and Credit Facilities (Summary of Debt Issuances) (Details) (USD $)		9 Months Ended																		9 Months Ended					9 Months Ended					9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014 April 2014 3.75% Senior Unsecured Notes Maturing April 2024 [Member] Unsecured Debt [Member]		Sep. 30, 2014 April 2014 0.612% Senior Unsecured Floating Notes Maturing April 2017 [Member] Unsecured Debt [Member]		Sep. 30, 2014 June 2014 11.870% Senior Unsecured Floating Notes Maturing May 2019 [Member] Unsecured Debt [Member]		Sep. 30, 2014 June 2014 13.680% Senior Unsecured Floating Notes Maturing May 2021 [Member] Unsecured Debt [Member]		Sep. 30, 2014 March 2014 0.854% Secured Credit Facility Maturing March 2017 [Member] Secured Debt [Member]		Sep. 30, 2014 July 2014 5.340% Secured Debt Maturing July 2036 [Member] Secured Debt [Member]		Sep. 30, 2014 March 2014 4.375% First Mortgage Bonds Maturing March 2044 [Member] First Mortgage Bonds [Member]		Sep. 30, 2014 March 2014 0.433% First Mortgage Bonds Maturing March 2017 [Member] First Mortgage Bonds [Member]		Sep. 30, 2014 Parent Company [Member]	Apr. 30, 2014 Parent Company [Member] Unsecured Debt [Member]	Sep. 30, 2014 Parent Company [Member] April 2014 3.75% Senior Unsecured Notes Maturing April 2024 [Member] Unsecured Debt [Member]		Sep. 30, 2014 Parent Company [Member] April 2014 0.612% Senior Unsecured Floating Notes Maturing April 2017 [Member] Unsecured Debt [Member]		Sep. 30, 2014 Duke Energy Progress [Member]	Sep. 30, 2014 Duke Energy Progress [Member] March 2014 4.375% First Mortgage Bonds Maturing March 2044 [Member] First Mortgage Bonds [Member]		Sep. 30, 2014 Duke Energy Progress [Member] March 2014 0.433% First Mortgage Bonds Maturing March 2017 [Member] First Mortgage Bonds [Member]		Sep. 30, 2014 Duke Energy Florida [Member]	Sep. 30, 2014 Duke Energy Florida [Member] March 2014 0.854% Secured Credit Facility Maturing March 2017 [Member] Secured Debt [Member]		Sep. 30, 2014 Duke Energy Ohio [Member] Unsecured Debt [Member]	Sep. 30, 2014 International Energy [Member] Unsecured Debt [Member]
Debt Instrument [Line Items]
Repayments of debt																																$ 402,000,000	$ 196,000,000
Debt issuance date		Apr. 01, 2014		Apr. 01, 2014		Jun. 01, 2014		Jun. 01, 2014		Mar. 01, 2014		Jul. 01, 2014		Mar. 01, 2014		Mar. 01, 2014				Apr. 01, 2014		Apr. 01, 2014			Mar. 01, 2014		Mar. 01, 2014			Mar. 01, 2014
Debt maturity date		Apr. 30, 2024		Apr. 30, 2017		May 31, 2019		May 31, 2021		Mar. 31, 2017		Jul. 31, 2036		Mar. 31, 2044		Mar. 31, 2017				Apr. 30, 2024		Apr. 30, 2017			Mar. 31, 2044		Mar. 31, 2017			Mar. 31, 2017
Interest rate		3.75%		0.612%		11.87%		13.68%		0.854%		5.34%		4.375%		0.433%				3.75%		0.612%			4.375%		0.433%			0.854%
Debt issuances	$ 2,222,000,000	$ 600,000,000	[1]	$ 400,000,000	[1]	$ 108,000,000	[2]	$ 110,000,000	[2]	$ 225,000,000	[3]	$ 129,000,000	[4]	$ 400,000,000	[5]	$ 250,000,000	[5]	$ 1,000,000,000	$ 1,000,000,000	$ 600,000,000	[1]	$ 400,000,000	[1]	$ 650,000,000	$ 400,000,000	[5]	$ 250,000,000	[5]	$ 225,000,000	$ 225,000,000	[3]

[1] Proceeds were used to redeem $402 million of tax-exempt bonds at Duke Energy Ohio, the repayment of outstanding commercial paper and for general corporate purposes. See Note 9 for additional information related to the redemption of Duke Energy Ohio's tax-exempt bonds.

[2] Proceeds were used to repay $196 million of debt for International Energy and for general corporate purposes.

[3] Relates to the securitization of accounts receivable at a subsidiary of Duke Energy Florida. Proceeds were used to repay short-term borrowings under the intercompany money pool borrowing arrangement and for general corporate purposes. See Note 13 for further details.

[4] Proceeds were used to fund a portion of Duke Energy's prior investment in the existing Wind Star renewables portfolio.

[5] Proceeds were used to repay short-term borrowings under the intercompany money pool borrowing arrangement and for general corporate purposes.