Investments in Debt and Equity Securities (Realized Gains and Losses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
FV-NI:
Realized gains	$ 201	$ 724	$ 366
Realized losses	316	141	174
AFS:
Realized gains	28	56	96
Realized losses	151	54	51
Duke Energy Carolinas
FV-NI:
Realized gains	124	440	64
Realized losses	177	96	99
AFS:
Realized gains	22	38	60
Realized losses	86	37	37
Progress Energy
FV-NI:
Realized gains	77	284	302
Realized losses	139	45	75
AFS:
Realized gains	6	16	24
Realized losses	48	14	13
Duke Energy Progress
FV-NI:
Realized gains	76	283	52
Realized losses	136	44	59
AFS:
Realized gains	6	15	24
Realized losses	44	13	13
Duke Energy Florida
FV-NI:
Realized gains	1	1	250
Realized losses	3	1	$ 16
AFS:
Realized gains		1
Realized losses	$ 4	$ 1