Fair Value Measurements (Other Fair Value Disclosure) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 69,309	$ 63,835
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	60,247	69,683
Piedmont Natural Gas and Progress Energy
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Unamortized debt discount (premium), net	1,190	1,250
Duke Energy Carolinas | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	14,222	13,275
Duke Energy Carolinas | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	12,614	15,101
Progress Energy | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	21,149	20,823
Progress Energy | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	18,744	23,751
Duke Energy Progress | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	11,090	10,249
Duke Energy Progress | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	9,495	11,252
Duke Energy Florida | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	8,417	8,482
Duke Energy Florida | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	7,528	9,772
Duke Energy Ohio | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,244	3,193
Duke Energy Ohio | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	2,891	3,570
Duke Energy Indiana | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	4,310	4,323
Duke Energy Indiana | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,821	5,067
Piedmont | Book Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	3,363	2,968
Piedmont | Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt	$ 2,857	$ 3,278