Debt and Credit Facilities (Summary of Debt Issuances) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Debt issuances	$ 9,127	$ 2,700
April 2016 Debt Maturing April 2023 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 350
Interest rate	2.875%
August 2016 Debt Maturing September 2021 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 750
Interest rate	1.80%
August 2016 Debt Maturing September 2026 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 1,500
Interest rate	2.65%
August 2016 Debt Maturing September 2046 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 1,500
Interest rate	3.75%
June 2016 Debt Maturing March 2020 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 183
Interest rate	1.196%
June 2016 Debt Maturing September 2022 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 150
Interest rate	1.731%
June 2016 Debt Maturing September 2029 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 436
Interest rate	2.538%
June 2016 Debt Maturing March 2033 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 250
Interest rate	2.858%
June 2016 Debt Maturing September 2036 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 275
Interest rate	3.112%
August 2016 Debt Tranche A Maturing June 2034 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 228
Interest rate	2.747%
August 2016 Debt Tranche B Maturing June 2020 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 105
Interest rate	2.747%
March 2016 Debt Maturing March 2023 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 500
Interest rate	2.50%
March 2016 Debt Maturing March 2046 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 500
Interest rate	3.875%
May 2016 Debt Maturing May 2046 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 500
Interest rate	3.75%
Repayments of Debt	$ 325
May 2016 Debt 2 Maturing May 2046 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Repayments of Debt	150
June 2016 Debt Maturing June 2046 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 250
Interest rate	3.70%
September 2016 Debt Maturing October 2046 3.4% [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600
Interest rate	3.40%
September 2016 Debt Maturing October 2046 3.7%[Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 450
Interest rate	3.70%
November 2016 Debt Maturing December 2026 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600
Interest rate	2.95%
Repayments of Debt	$ 350
November 2015 Debt Maturing April 2024 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances		$ 400
Interest rate		3.75%
Repayments of Debt		$ 300
November 2015 Debt Maturing December 2045 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances		$ 600
Interest rate		4.80%
Repayments of Debt		$ 300
March 2015 Debt Maturing June 2045 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances		$ 500
Interest rate		3.75%
Repayments of Debt		$ 500
August 2015 Debt Maturing August 2025 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances		$ 500
Interest rate		3.25%
Repayments of Debt		$ 400
August 2015 Debt Maturing August 2045 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances		$ 700
Interest rate		4.20%
Repayments of Debt		$ 400
Parent Company [Member]
Debt Instrument [Line Items]
Debt issuances	4,100	1,000
Parent Company [Member] | April 2016 Debt Maturing April 2023 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 350
Interest rate	2.875%
Parent Company [Member] | August 2016 Debt Maturing September 2021 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 750
Interest rate	1.80%
Parent Company [Member] | August 2016 Debt Maturing September 2026 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 1,500
Interest rate	2.65%
Parent Company [Member] | August 2016 Debt Maturing September 2046 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 1,500
Interest rate	3.75%
Parent Company [Member] | November 2015 Debt Maturing April 2024 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances		$ 400
Interest rate		3.75%
Repayments of Debt		$ 300
Parent Company [Member] | November 2015 Debt Maturing December 2045 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Debt issuances		$ 600
Interest rate		4.80%
Repayments of Debt		$ 300
Duke Energy Carolinas [Member]
Debt Instrument [Line Items]
Debt issuances	$ 1,600	500
Duke Energy Carolinas [Member] | March 2016 Debt Maturing March 2023 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 500
Interest rate	2.50%
Duke Energy Carolinas [Member] | March 2016 Debt Maturing March 2046 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 500
Interest rate	3.875%
Duke Energy Carolinas [Member] | November 2016 Debt Maturing December 2026 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600
Interest rate	2.95%
Repayments of Debt	$ 350
Duke Energy Carolinas [Member] | March 2015 Debt Maturing June 2045 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances		$ 500
Interest rate		3.75%
Repayments of Debt		$ 500
Duke Energy Progress [Member]
Debt Instrument [Line Items]
Debt issuances	450	1,200
Duke Energy Progress [Member] | September 2016 Debt Maturing October 2046 3.7%[Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 450
Interest rate	3.70%
Duke Energy Progress [Member] | March 2015 Debt Maturing June 2045 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances		0
Duke Energy Progress [Member] | August 2015 Debt Maturing August 2025 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances		$ 500
Interest rate		3.25%
Repayments of Debt		$ 400
Duke Energy Progress [Member] | August 2015 Debt Maturing August 2045 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances		$ 700
Interest rate		4.20%
Repayments of Debt		$ 400
Duke Energy Florida [Member]
Debt Instrument [Line Items]
Debt issuances	$ 1,894
Duke Energy Florida [Member] | June 2016 Debt Maturing March 2020 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 183
Interest rate	1.196%
Duke Energy Florida [Member] | June 2016 Debt Maturing September 2022 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 150
Interest rate	1.731%
Duke Energy Florida [Member] | June 2016 Debt Maturing September 2029 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 436
Interest rate	2.538%
Duke Energy Florida [Member] | June 2016 Debt Maturing March 2033 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 250
Interest rate	2.858%
Duke Energy Florida [Member] | June 2016 Debt Maturing September 2036 [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Debt issuances	$ 275
Interest rate	3.112%
Duke Energy Florida [Member] | September 2016 Debt Maturing October 2046 3.4% [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 600
Interest rate	3.40%
Duke Energy Ohio [Member]
Debt Instrument [Line Items]
Debt issuances	$ 250
Duke Energy Ohio [Member] | June 2016 Debt Maturing June 2046 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 250
Interest rate	3.70%
Duke Energy Indiana [Member]
Debt Instrument [Line Items]
Debt issuances	$ 500
Duke Energy Indiana [Member] | May 2016 Debt Maturing May 2046 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Debt issuances	$ 500
Interest rate	3.75%
Repayments of Debt	$ 325
Duke Energy Indiana [Member] | May 2016 Debt 2 Maturing May 2046 [Member] | First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 150