Summary of Significant Accounting Policies (Accounts Payable and Supplier Invoices Sold) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	$ 50	$ 87
Invoices confirmed during the period	156	228
Confirmed invoices paid during the period	(193)	(265)
Confirmed obligations outstanding at end of period	13	50
Duke Energy Carolinas
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	0	6
Invoices confirmed during the period	0	24
Confirmed invoices paid during the period	0	(30)
Confirmed obligations outstanding at end of period	0	0
Progress Energy
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	3	19
Invoices confirmed during the period	4	58
Confirmed invoices paid during the period	(6)	(74)
Confirmed obligations outstanding at end of period	1	3
Duke Energy Progress
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	0	8
Invoices confirmed during the period	0	22
Confirmed invoices paid during the period	0	(30)
Confirmed obligations outstanding at end of period	0	0
Duke Energy Florida
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	3	11
Invoices confirmed during the period	4	36
Confirmed invoices paid during the period	(6)	(44)
Confirmed obligations outstanding at end of period	1	3
Duke Energy Ohio
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	0	5
Invoices confirmed during the period	0	7
Confirmed invoices paid during the period	0	(12)
Confirmed obligations outstanding at end of period	0	0
Duke Energy Indiana
Payables [Line Items]
Invoices confirmed during the period		0
Confirmed invoices paid during the period		0
Piedmont
Payables [Line Items]
Confirmed obligations outstanding at beginning of period	47	57
Invoices confirmed during the period	152	139
Confirmed invoices paid during the period	(187)	(149)
Confirmed obligations outstanding at end of period	$ 12	$ 47