Summary of Significant Accounting Policies (Accounts Payable and Supplier Invoices Sold) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	$ 87	$ 19
Invoices confirmed during the period	228	283
Confirmed invoices paid during the period	(265)	(215)
Confirmed obligations outstanding at end of period	50	87
Duke Energy Carolinas
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	6	0
Invoices confirmed during the period	24	29
Confirmed invoices paid during the period	(30)	(23)
Confirmed obligations outstanding at end of period	0	6
Progress Energy
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	19	9
Invoices confirmed during the period	58	76
Confirmed invoices paid during the period	(74)	(66)
Confirmed obligations outstanding at end of period	3	19
Duke Energy Progress
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	8	0
Invoices confirmed during the period	22	26
Confirmed invoices paid during the period	(30)	(18)
Confirmed obligations outstanding at end of period	0	8
Duke Energy Florida
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	11	9
Invoices confirmed during the period	36	50
Confirmed invoices paid during the period	(44)	(48)
Confirmed obligations outstanding at end of period	3	11
Duke Energy Ohio
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	5	6
Invoices confirmed during the period	7	32
Confirmed invoices paid during the period	(12)	(33)
Confirmed obligations outstanding at end of period	0	5
Duke Energy Indiana
Payables [Line Items]
Invoices confirmed during the period		2
Confirmed invoices paid during the period		(2)
Piedmont
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	57	4
Invoices confirmed during the period	139	145
Confirmed invoices paid during the period	(149)	(92)
Confirmed obligations outstanding at end of period	$ 47	$ 57