Business Segments (Business Segment Data) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Operating revenues	$ 6,150	$ 5,949
Segment income (loss)	953	899
Less: Noncontrolling interests	(51)	(48)
Add: Preferred stock dividend	39	39
Net Income	941	890
Segment assets	163,465		$ 162,388
Unregulated operating revenue	(182)	(187)
Incurred costs	1,402	1,339
Equity in (losses) earnings of unconsolidated affiliates	17	(44)
Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	5,273	5,174
Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	752	640
Gas Utilities and Infrastructure | Asset Impairment for Regulatory Action
Segment Reporting Information [Line Items]
Equity in (losses) earnings of unconsolidated affiliates	6
Commercial Renewables
Segment Reporting Information [Line Items]
Operating revenues	119	129
Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	6,144	5,943
Other
Segment Reporting Information [Line Items]
Operating revenues	6	6
Other
Segment Reporting Information [Line Items]
Severance charge reversal		98
Operating Segments | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	5,281	5,183
Segment income (loss)	820	705
Segment assets	138,734
Operating Segments | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	775	664
Segment income (loss)	245	249
Segment assets	14,139
Operating Segments | Commercial Renewables
Segment Reporting Information [Line Items]
Operating revenues	119	129
Segment income (loss)	27	57
Segment assets	6,894
Operating Segments | Commercial Renewables | Texas Storm Uri
Segment Reporting Information [Line Items]
Segment income (loss)	(35)
Less: Noncontrolling interests	12
Unregulated operating revenue	8
Incurred costs	2
Equity in (losses) earnings of unconsolidated affiliates	29
Operating Segments | Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	6,175	5,976
Segment income (loss)	1,092	1,011
Segment assets	159,767
Other | Other
Segment Reporting Information [Line Items]
Operating revenues	26	23
Segment income (loss)	(139)	(112)
Segment assets	3,710
Eliminations
Segment Reporting Information [Line Items]
Operating revenues	(51)	(50)
Segment assets	(12)
Eliminations | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	8	9
Eliminations | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	23	24
Eliminations | Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	31	33
Eliminations | Other
Segment Reporting Information [Line Items]
Operating revenues	20	17
Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	532	498
Segment income (loss)	91	65
Segment assets	10,141		$ 10,025
Incurred costs	108	123
Duke Energy Ohio | Operating Segments | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	363	346
Segment income (loss)	50	30
Segment assets	6,544
Duke Energy Ohio | Operating Segments | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	169	152
Segment income (loss)	43	36
Segment assets	3,575
Duke Energy Ohio | Operating Segments | Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	532	498
Segment income (loss)	93	66
Segment assets	10,119
Duke Energy Ohio | Other | Other
Segment Reporting Information [Line Items]
Segment income (loss)	(2)	$ (1)
Segment assets	29
Duke Energy Ohio | Eliminations
Segment Reporting Information [Line Items]
Segment assets	$ (7)