Investments in Debt and Equity Securities (Maturities) (Details) $ in Millions	Dec. 31, 2022 USD ($)
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	$ 137
Due after one through five years	807
Due after five through 10 years	469
Due after 10 years	1,402
Total	2,815
Duke Energy Carolinas
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	7
Due after one through five years	287
Due after five through 10 years	230
Due after 10 years	774
Total	1,298
Progress Energy
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	89
Due after one through five years	443
Due after five through 10 years	193
Due after 10 years	552
Total	1,277
Duke Energy Progress
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	24
Due after one through five years	244
Due after five through 10 years	178
Due after 10 years	517
Total	963
Duke Energy Florida
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	65
Due after one through five years	199
Due after five through 10 years	15
Due after 10 years	35
Total	314
Duke Energy Indiana
Debt Securities, Available-for-sale [Line Items]
Due in one year or less	8
Due after one through five years	22
Due after five through 10 years	6
Due after 10 years	24
Total	$ 60