Summary of Significant Accounting Policies (Inventory) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Public Utilities, Inventory [Line Items]
Materials and supplies	$ 2,604	$ 2,309
Coal	620	486
Natural gas, oil and other	360	316
Total inventory	3,584	3,111
Duke Energy Carolinas
Public Utilities, Inventory [Line Items]
Materials and supplies	876	793
Coal	253	195
Natural gas, oil and other	35	38
Total inventory	1,164	1,026
Progress Energy
Public Utilities, Inventory [Line Items]
Materials and supplies	1,232	1,067
Coal	190	167
Natural gas, oil and other	157	164
Total inventory	1,579	1,398
Duke Energy Progress
Public Utilities, Inventory [Line Items]
Materials and supplies	819	729
Coal	99	94
Natural gas, oil and other	88	98
Total inventory	1,006	921
Duke Energy Florida
Public Utilities, Inventory [Line Items]
Materials and supplies	413	338
Coal	91	73
Natural gas, oil and other	69	66
Total inventory	573	477
Duke Energy Ohio
Public Utilities, Inventory [Line Items]
Materials and supplies	105	80
Coal	34	19
Natural gas, oil and other	5	17
Total inventory	144	116
Duke Energy Indiana
Public Utilities, Inventory [Line Items]
Materials and supplies	342	311
Coal	144	105
Natural gas, oil and other	3	2
Total inventory	489	418
Piedmont
Public Utilities, Inventory [Line Items]
Materials and supplies	12	14
Natural gas, oil and other	160	95
Total inventory	$ 172	$ 109