Employee Benefit Plans (Components of Net Periodic Pension Costs) (Details) - Qualified Pension Plans - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 28	$ 30
Interest cost on projected benefit obligation	82	86
Expected return on plan assets	(154)	(147)
Amortization of actuarial loss	8	2
Amortization of prior service credit	(3)	(3)
Amortization of settlement charges	5	5
Net periodic pension costs	(34)	(27)
Duke Energy Carolinas
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	9	10
Interest cost on projected benefit obligation	20	21
Expected return on plan assets	(41)	(40)
Amortization of actuarial loss	2	0
Amortization of prior service credit	0	0
Amortization of settlement charges	2	2
Net periodic pension costs	(8)	(7)
Progress Energy
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	8	9
Interest cost on projected benefit obligation	26	27
Expected return on plan assets	(54)	(50)
Amortization of actuarial loss	2	1
Amortization of prior service credit	0	0
Amortization of settlement charges	1	1
Net periodic pension costs	(17)	(12)
Duke Energy Progress
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	5	5
Interest cost on projected benefit obligation	12	12
Expected return on plan assets	(25)	(23)
Amortization of actuarial loss	1	0
Amortization of prior service credit	0	0
Amortization of settlement charges	1	1
Net periodic pension costs	(6)	(5)
Duke Energy Florida
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	3	3
Interest cost on projected benefit obligation	14	14
Expected return on plan assets	(29)	(26)
Amortization of actuarial loss	1	1
Amortization of prior service credit	0	0
Amortization of settlement charges	0	0
Net periodic pension costs	(11)	(8)
Duke Energy Ohio
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	1	1
Interest cost on projected benefit obligation	4	4
Expected return on plan assets	(6)	(6)
Amortization of actuarial loss	0	0
Amortization of prior service credit	0	0
Amortization of settlement charges	0	0
Net periodic pension costs	(1)	(1)
Duke Energy Indiana
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	2	1
Interest cost on projected benefit obligation	6	7
Expected return on plan assets	(10)	(10)
Amortization of actuarial loss	1	1
Amortization of prior service credit	0	0
Amortization of settlement charges	0	0
Net periodic pension costs	(1)	(1)
Piedmont
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	1	1
Interest cost on projected benefit obligation	2	2
Expected return on plan assets	(5)	(5)
Amortization of actuarial loss	1	0
Amortization of prior service credit	(2)	(2)
Amortization of settlement charges	1	1
Net periodic pension costs	$ (2)	$ (3)