Organization and Basis of Presentation (Confirmed Obligations) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Duke Energy (Parent)
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	$ 76	$ 52	$ 50	$ 87
Invoices confirmed during the period	63	55	120	114
Confirmed invoices paid during the period	(111)	(67)	(142)	(161)
Confirmed obligations at end of period	28	40	28	40
Duke Energy Carolinas
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	0	7	0	6
Invoices confirmed during the period	0	10	0	20
Confirmed invoices paid during the period	0	(12)	0	(21)
Confirmed obligations at end of period	0	5	0	5
Progress Energy
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	2	15	3	19
Invoices confirmed during the period	0	20	1	42
Confirmed invoices paid during the period	(2)	(21)	(4)	(47)
Confirmed obligations at end of period	0	14	0	14
Duke Energy Progress
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	0	6	0	8
Invoices confirmed during the period	0	12	0	23
Confirmed invoices paid during the period	0	(6)	0	(19)
Confirmed obligations at end of period	0	12	0	12
Duke Energy Florida
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	2	9	3	11
Invoices confirmed during the period	0	8	1	19
Confirmed invoices paid during the period	(2)	(15)	(4)	(28)
Confirmed obligations at end of period	0	2	0	2
Duke Energy Ohio
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	0	0	0	5
Invoices confirmed during the period	0	2	0	3
Confirmed invoices paid during the period	0	0	0	(6)
Confirmed obligations at end of period	0	2	0	2
Duke Energy Indiana
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	0	0	0	0
Invoices confirmed during the period	0	0	0	0
Confirmed invoices paid during the period	0	0	0	0
Confirmed obligations at end of period	0	0	0	0
Piedmont
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	74	29	47	57
Invoices confirmed during the period	63	24	119	49
Confirmed invoices paid during the period	(109)	(34)	(138)	(87)
Confirmed obligations at end of period	$ 28	$ 19	$ 28	$ 19