Organization and Basis of Presentation (Confirmed Obligations) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Duke Energy (Parent)
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	$ 87	$ 19
Invoices confirmed during the period	59	31
Confirmed invoices paid during the period	(94)	(31)
Confirmed obligations at end of period	52	19
Duke Energy Carolinas
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	6
Invoices confirmed during the period	10	2
Confirmed invoices paid during the period	(9)	(1)
Confirmed obligations at end of period	7	1
Progress Energy
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	19	9
Invoices confirmed during the period	22	11
Confirmed invoices paid during the period	(26)	(11)
Confirmed obligations at end of period	15	9
Duke Energy Progress
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	8
Invoices confirmed during the period	11	2
Confirmed invoices paid during the period	(13)	(1)
Confirmed obligations at end of period	6	1
Duke Energy Florida
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	11	9
Invoices confirmed during the period	11	9
Confirmed invoices paid during the period	(13)	(10)
Confirmed obligations at end of period	9	8
Duke Energy Ohio
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	5	6
Invoices confirmed during the period	1	6
Confirmed invoices paid during the period	(6)	(8)
Confirmed obligations at end of period		4
Duke Energy Indiana
Contractual Obligations [Roll Forward]
Invoices confirmed during the period		2
Confirmed invoices paid during the period		(1)
Confirmed obligations at end of period		1
Piedmont
Contractual Obligations [Roll Forward]
Confirmed obligations at beginning of period	57	4
Invoices confirmed during the period	25	11
Confirmed invoices paid during the period	(53)	(10)
Confirmed obligations at end of period	$ 29	$ 5