Debt and Credit Facilities (Summary of Debt Issuances) (Details) - USD ($)	1 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt issuances		$ 5,550,000,000	$ 6,210,000,000
Repayments of long-term debt		$ 4,506,000,000	$ 3,476,000,000	$ 2,906,000,000
May 2020 Debt Issuance Due June 2030 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		2.45%
Debt issuances		$ 500,000,000
May 2020 Debt Issuance Due June 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		2.125%
Debt issuances		$ 400,000,000
May 2020 Debt Issuance Due June 2050 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		3.35%
Debt issuances		$ 400,000,000
August 2020 Debt Issuance Due February 2022 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		0.40%
Debt issuances		$ 700,000,000
September 2020 Debt Issuance Due September 2025 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		0.90%
Debt issuances		$ 650,000,000
September 2020 Debt Issuance Due June 2030 | Unsecured Debt
Debt Instrument [Line Items]
Interest Rate		2.45%
Debt issuances		$ 350,000,000
January 2020 Debt Issuance 2.450% Coupon Due 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		2.45%
Debt issuances		$ 500,000,000
January 2020 Debt Issuance 3.20% Due August 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		3.20%
Debt issuances		$ 400,000,000
March 2020 Debt Issuance 2.750% Due April 2050 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		2.75%
Debt issuances		$ 550,000,000
June 2020 Debt Issuance Due June 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		1.75%
Debt issuances		$ 500,000,000
August 2020 Debt Issuance Due August 2050 | First Mortgage Bonds
Debt Instrument [Line Items]
Interest Rate		2.50%
Debt issuances		$ 600,000,000
March 2019 Debt Issuance Due March 2022
Debt Instrument [Line Items]
Interest Rate			2.538%
March 2019 Debt Issuance Due March 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 300,000,000
March 2019 Debt Issuance 3.227% Coupon Due 2022
Debt Instrument [Line Items]
Interest Rate			3.227%
March 2019 Debt Issuance 3.227% Coupon Due 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 300,000,000
May 2019 Debt Issuance 3.500% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.50%
May 2019 Debt Issuance 3.500% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 600,000,000
June 2019 Debt Issuance 3.400% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.40%
June 2019 Debt Issuance 3.400% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 600,000,000
June 2019 Debt Issuance 4.200% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			4.20%
June 2019 Debt Issuance 4.200% Coupon Due 2049 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 600,000,000
July 2019 Debt Issuance 4.320% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			4.32%
July 2019 Debt Issuance 4.320% Coupon Due 2049 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 40,000,000
September 2019 Debt Issuance 3.230% Coupon Due 2025
Debt Instrument [Line Items]
Interest Rate			3.23%
September 2019 Debt Issuance 3.230% Coupon Due 2025 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 95,000,000
September 2019 Debt Issuance 3.560% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.56%
September 2019 Debt Issuance 3.560% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 75,000,000
November 2019 Debt Issuance 2.167% Coupon Due 2021
Debt Instrument [Line Items]
Interest Rate			2.167%
November 2019 Debt Issuance 2.167% Coupon Due 2021 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			$ 200,000,000
January 2019 Debt Issuance 3.650% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.65%
January 2019 Debt Issuance 3.650% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 400,000,000
January 2019 Debt Issuance 4.300% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			4.30%
January 2019 Debt Issuance 4.300% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 400,000,000
March 2019 Debt Issuance 3.450% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			3.45%
March 2019 Debt Issuance 3.450% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 600,000,000
August 2019 Debt Issuance 2.450% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			2.45%
August 2019 Debt Issuance 2.450% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 450,000,000
August 2019 Debt Issuance 3.200% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			3.20%
August 2019 Debt Issuance 3.200% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 350,000,000
September 2019 Debt Issuance 3.250% Coupon Due 2049
Debt Instrument [Line Items]
Interest Rate			3.25%
September 2019 Debt Issuance 3.250% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 500,000,000
November 2019 Debt Issuance 2.500% Coupon Due 2029
Debt Instrument [Line Items]
Interest Rate			2.50%
November 2019 Debt Issuance 2.500% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			$ 700,000,000
Parent Company
Debt Instrument [Line Items]
Debt issuances		1,500,000,000	1,800,000,000
Parent Company | May 2020 Debt Issuance Due June 2030 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		500,000,000
Parent Company | September 2020 Debt Issuance Due September 2025 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		650,000,000
Parent Company | September 2020 Debt Issuance Due June 2030 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		350,000,000
Parent Company | March 2019 Debt Issuance Due March 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			300,000,000
Parent Company | March 2019 Debt Issuance 3.227% Coupon Due 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			300,000,000
Parent Company | June 2019 Debt Issuance 3.400% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			600,000,000
Parent Company | June 2019 Debt Issuance 4.200% Coupon Due 2049 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			600,000,000
Duke Energy Carolinas
Debt Instrument [Line Items]
Debt issuances		900,000,000	800,000,000
Repayments of long-term debt		813,000,000	6,000,000	1,205,000,000
Duke Energy Carolinas | January 2020 Debt Issuance 2.450% Coupon Due 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		500,000,000
Duke Energy Carolinas | January 2020 Debt Issuance 3.20% Due August 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		400,000,000
Duke Energy Carolinas | Bonds Maturing June 2020, 4.300% Coupon | First Mortgage Bonds
Debt Instrument [Line Items]
Repayments of long-term debt	$ 450,000,000
Duke Energy Carolinas | August 2019 Debt Issuance 2.450% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			450,000,000
Duke Energy Carolinas | August 2019 Debt Issuance 3.200% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			350,000,000
Duke Energy Progress
Debt Instrument [Line Items]
Debt issuances		1,300,000,000	600,000,000
Repayments of long-term debt		1,085,000,000	605,000,000	3,000,000
Duke Energy Progress | Term Loan
Debt Instrument [Line Items]
Repayments of long-term debt		700,000,000
Duke Energy Progress | August 2020 Debt Issuance Due February 2022 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		700,000,000
Duke Energy Progress | August 2020 Debt Issuance Due August 2050 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		600,000,000
Duke Energy Progress | Bonds Due September 2020 | First Mortgage Bonds
Debt Instrument [Line Items]
Repayments of long-term debt		300,000,000
Duke Energy Progress | March 2019 Debt Issuance 3.450% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			600,000,000
Duke Energy Florida
Debt Instrument [Line Items]
Debt issuances		500,000,000	900,000,000
Repayments of long-term debt		572,000,000	262,000,000	769,000,000
Duke Energy Florida | June 2020 Debt Issuance Due June 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		500,000,000
Duke Energy Florida | November 2019 Debt Issuance 2.167% Coupon Due 2021 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			200,000,000
Duke Energy Florida | November 2019 Debt Issuance 2.500% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			700,000,000
Duke Energy Ohio
Debt Instrument [Line Items]
Debt issuances		400,000,000	1,010,000,000
Repayments of long-term debt			551,000,000	3,000,000
Duke Energy Ohio | May 2020 Debt Issuance Due June 2030 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		400,000,000
Duke Energy Ohio | July 2019 Debt Issuance 4.320% Coupon Due 2049 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			40,000,000
Duke Energy Ohio | September 2019 Debt Issuance 3.230% Coupon Due 2025 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			95,000,000
Duke Energy Ohio | September 2019 Debt Issuance 3.560% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			75,000,000
Duke Energy Ohio | January 2019 Debt Issuance 3.650% Coupon Due 2029 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			400,000,000
Duke Energy Ohio | January 2019 Debt Issuance 4.300% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			400,000,000
Duke Energy Ohio | April 2019 First Mortgage Bonds
Debt Instrument [Line Items]
Repayments of long-term debt			450,000,000
Duke Energy Ohio | Debentures Due October 2019
Debt Instrument [Line Items]
Repayments of long-term debt			100,000,000
Duke Energy Indiana
Debt Instrument [Line Items]
Debt issuances		550,000,000	500,000,000
Repayments of long-term debt		513,000,000	213,000,000	$ 3,000,000
Duke Energy Indiana | March 2020 Debt Issuance 2.750% Due April 2050 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances		550,000,000
Duke Energy Indiana | Bonds Due July 2020 | First Mortgage Bonds
Debt Instrument [Line Items]
Repayments of long-term debt		500,000,000
Duke Energy Indiana | September 2019 Debt Issuance 3.250% Coupon Due 2049 | First Mortgage Bonds
Debt Instrument [Line Items]
Debt issuances			500,000,000
Duke Energy Indiana | Pollution Control Bonds
Debt Instrument [Line Items]
Repayments of long-term debt			150,000,000
Piedmont
Debt Instrument [Line Items]
Debt issuances		400,000,000	600,000,000
Repayments of long-term debt			350,000,000
Piedmont | May 2020 Debt Issuance Due June 2050 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances		400,000,000
Piedmont | May 2019 Debt Issuance 3.500% Coupon Due 2029 | Unsecured Debt
Debt Instrument [Line Items]
Debt issuances			600,000,000
Piedmont | Senior Unsecured Term Loan Facility Due September 2019
Debt Instrument [Line Items]
Repayments of long-term debt			$ 350,000,000
Duke Energy (Parent) | Term Loan Due March 2021
Debt Instrument [Line Items]
Repayments of long-term debt		1,700,000,000
Revolving Credit Facility | Duke Energy (Parent)
Debt Instrument [Line Items]
Repayments of long-term debt		$ 500,000,000