Summary of Significant Accounting Policies (Other Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Current Liabilities
Organization And Basis Of Presentation [Line Items]
Accrued compensation	$ 915	$ 662
Other accrued liabilities	649	1,455
Duke Energy Carolinas | Current Liabilities
Organization And Basis Of Presentation [Line Items]
Accrued compensation	277	213
Duke Energy Progress | Current Liabilities
Organization And Basis Of Presentation [Line Items]
Other accrued liabilities	163	132
Customer deposits	144	144
Duke Energy Florida | Current Liabilities
Organization And Basis Of Presentation [Line Items]
Other accrued liabilities	89	81
Customer deposits	200	203
Duke Energy Ohio | Current Liabilities
Organization And Basis Of Presentation [Line Items]
Collateral liabilities	57	41
Duke Energy Ohio | Current Assets
Organization And Basis Of Presentation [Line Items]
Gas Storage	$ 25	$ 21