Business Segments (Business Segment Data) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Operating revenues	$ 6,951	$ 6,721	$ 18,859	$ 18,091
Segment income (loss)	1,366	1,265	3,070	1,347
Less: Noncontrolling interests	129	70	247	208
Add: Preferred stock dividend	39	39	92	93
Net Income	1,276	1,234	2,915	1,232
Segment assets	167,007		167,007		$ 162,388
Equity in earnings (losses) of unconsolidated affiliates	22	(80)	14	(2,004)
Impairment of assets and other charges	211	28	342	36
Income (loss) before taxes	1,366	1,339	3,125	1,158
Nonregulated electric and other	193	192	573	574
Incurred costs	1,507	1,450	4,319	4,142
Duke Energy Carolinas
Segment Reporting Information [Line Items]
Operating revenues	2,104	2,058	5,430	5,416
Segment assets	46,221		46,221		45,048
Impairment of assets and other charges	163	20	238	22
Income (loss) before taxes	549	631	1,110	1,306
Incurred costs	471	402	1,347	1,218
Duke Energy Progress
Segment Reporting Information [Line Items]
Operating revenues	1,667	1,626	4,417	4,207
Segment assets	34,557		34,557		33,733
Impairment of assets and other charges	42	5	60	5
Income (loss) before taxes	400	357	850	790
Incurred costs	368	348	1,092	970
Piedmont
Segment Reporting Information [Line Items]
Operating revenues	195	162	1,016	871
Segment assets	9,024		9,024		8,615
Equity in earnings (losses) of unconsolidated affiliates			7	7
Impairment of assets and other charges	4	7	9	7
Income (loss) before taxes	(32)	(30)	191	161
Incurred costs	77	75	231	234
Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	506	473	1,494	1,394
Segment income (loss)	58	70	188	201
Segment assets	10,505		10,505		$ 10,025
Impairment of assets and other charges			5
Income (loss) before taxes	67	84	222	241
Incurred costs	116	115	335	333
Impairment charges
Segment Reporting Information [Line Items]
Impairment of assets and other charges			139
Operations, maintenance and other
Segment Reporting Information [Line Items]
Impairment of assets and other charges			28
Depreciation and amortization
Segment Reporting Information [Line Items]
Impairment of assets and other charges			17
Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	6,560	6,371	17,161	16,571
Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	266	217	1,323	1,122
Gas Utilities and Infrastructure | Asset Impairment for Regulatory Action
Segment Reporting Information [Line Items]
Equity in earnings (losses) of unconsolidated affiliates			(19)
Commercial Renewables
Segment Reporting Information [Line Items]
Operating revenues	117	126	355	378
Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	6,943	6,714	18,839	18,071
Other
Segment Reporting Information [Line Items]
Operating revenues	8	7	20	20
Operating Segments | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	6,569	6,379	17,185	16,596
Segment income (loss)	1,425	1,381	3,180	2,839
Segment assets	141,565		141,565
Operating Segments | Electric Utilities and Infrastructure | Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	413	394	1,119	1,070
Segment income (loss)	48	63	122	137
Segment assets	6,716		6,716
Operating Segments | Electric Utilities and Infrastructure | Impairment charges | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Impairment of assets and other charges	160	19	160	19
Operating Segments | Electric Utilities and Infrastructure | Impairment charges | Duke Energy Progress
Segment Reporting Information [Line Items]
Impairment of assets and other charges	42		42
Operating Segments | Electric Utilities and Infrastructure | Impairment charges | Duke Energy Progress | ACP
Segment Reporting Information [Line Items]
Impairment of assets and other charges		5		5
Operating Segments | Electric Utilities and Infrastructure | Operations, maintenance and other | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Income (loss) before taxes	5	8	5	8
Operating Segments | Electric Utilities and Infrastructure | Operations, maintenance and other | Duke Energy Progress
Segment Reporting Information [Line Items]
Income (loss) before taxes	7		7
Operating Segments | Electric Utilities and Infrastructure | Other income and expense | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Income (loss) before taxes	77		77
Operating Segments | Electric Utilities and Infrastructure | Other income and expense | Duke Energy Progress
Segment Reporting Information [Line Items]
Income (loss) before taxes	34		34
Operating Segments | Electric Utilities and Infrastructure | Regulated electric operating revenues | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Income (loss) before taxes	13		13
Operating Segments | Electric Utilities and Infrastructure | Regulated electric operating revenues | Duke Energy Progress
Segment Reporting Information [Line Items]
Income (loss) before taxes	15		15
Operating Segments | Electric Utilities and Infrastructure | Interest expense | Duke Energy Carolinas
Segment Reporting Information [Line Items]
Income (loss) before taxes	3		3
Operating Segments | Electric Utilities and Infrastructure | Interest expense | Duke Energy Progress
Segment Reporting Information [Line Items]
Income (loss) before taxes	5		5
Operating Segments | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	289	241	1,391	1,194
Segment income (loss)	(3)	(73)	259	(1,400)
Segment assets	14,692		14,692
Equity in earnings (losses) of unconsolidated affiliates	3	78		2,000
Operating Segments | Gas Utilities and Infrastructure | Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	93	79	375	324
Segment income (loss)	11	9	77	68
Segment assets	3,783		3,783
Operating Segments | Gas Utilities and Infrastructure | Impairment charges
Segment Reporting Information [Line Items]
Impairment of assets and other charges	8
Operating Segments | Gas Utilities and Infrastructure | Impairment charges | Piedmont
Segment Reporting Information [Line Items]
Impairment of assets and other charges		7
Operating Segments | Gas Utilities and Infrastructure | Operations, maintenance and other
Segment Reporting Information [Line Items]
Income (loss) before taxes	1
Operating Segments | Commercial Renewables
Segment Reporting Information [Line Items]
Operating revenues	117	126	355	378
Segment income (loss)	78	60	152	207
Segment assets	7,037		7,037
Operating Segments | Commercial Renewables | Texas Storm Uri
Segment Reporting Information [Line Items]
Less: Noncontrolling interests			12
Equity in earnings (losses) of unconsolidated affiliates			29
Income (loss) before taxes			(35)
Nonregulated electric and other			8
Incurred costs			2
Operating Segments | Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	6,975	6,746	18,931	18,168
Segment income (loss)	1,500	1,368	3,591	1,646
Segment assets	163,294		163,294
Operating Segments | Total Reportable Segments | Duke Energy Ohio
Segment Reporting Information [Line Items]
Operating revenues	506	473	1,494	1,394
Segment income (loss)	59	72	199	205
Segment assets	10,499		10,499
Other | Operations, maintenance and other
Segment Reporting Information [Line Items]
Income (loss) before taxes				98
Other | Other
Segment Reporting Information [Line Items]
Operating revenues	28	24	81	73
Segment income (loss)	(134)	(103)	(521)	(299)
Segment assets	3,717		3,717
Other | Other | Duke Energy Ohio
Segment Reporting Information [Line Items]
Segment income (loss)	(1)	(2)	(11)	(4)
Segment assets	27		27
Eliminations
Segment Reporting Information [Line Items]
Operating revenues	(52)	(49)	(153)	(150)
Segment assets	(4)		(4)
Eliminations | Duke Energy Ohio
Segment Reporting Information [Line Items]
Segment assets	(21)		(21)
Eliminations | Electric Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	9	8	24	25
Eliminations | Gas Utilities and Infrastructure
Segment Reporting Information [Line Items]
Operating revenues	23	24	68	72
Eliminations | Total Reportable Segments
Segment Reporting Information [Line Items]
Operating revenues	32	32	92	97
Eliminations | Other
Segment Reporting Information [Line Items]
Operating revenues	$ 20	$ 17	$ 61	$ 53