Fair Value Measurements (Other Fair Value Disclosure) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 75,387	$ 69,751
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	65,070	61,986
Piedmont Natural Gas and Progress Energy
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized debt discount (premium), net	1,100	1,200
Duke Energy Carolinas | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	15,995	14,266
Duke Energy Carolinas | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	13,973	12,943
Progress Energy | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	23,281	22,439
Progress Energy | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	20,417	20,467
Duke Energy Progress | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	11,718	11,087
Duke Energy Progress | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	9,808	9,689
Duke Energy Florida | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	9,920	9,709
Duke Energy Florida | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	8,892	8,991
Duke Energy Ohio | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,692	3,245
Duke Energy Ohio | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,264	2,927
Duke Energy Indiana | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	4,504	4,307
Duke Energy Indiana | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,874	3,913
Piedmont | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,713	3,363
Piedmont | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 3,123	$ 2,940