Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 6,658	$ 6,792	$ 17,817	$ 18,485
Revenue from sources other than contracts with customers	63	148	274	491
Total operating revenues	6,721	6,940	18,091	18,976
Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6,378	6,492	16,538	17,074
Total operating revenues	6,371	6,569	16,571	17,357
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,936	2,923	7,451	7,597
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,804	1,885	4,691	4,896
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	797	869	2,148	2,339
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	603	617	1,535	1,685
Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	238	198	713	557
Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	216	223	1,089	1,236
Total operating revenues	217	225	1,122	1,239
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	112	113	631	673
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	64	68	308	359
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	24	26	92	103
Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	16	16	58	101
Commercial Renewables
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	57	69	170	157
Total operating revenues	126	138	378	362
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	7	8	20	18
Total operating revenues	7	8	20	18
Duke Energy Carolinas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,068	2,140	5,423	5,535
Revenue from sources other than contracts with customers	(10)	22	(7)	84
Total operating revenues	2,058	2,162	5,416	5,619
Duke Energy Carolinas | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,068	2,140	5,423	5,535
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	883	892	2,316	2,331
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	664	687	1,720	1,714
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	342	372	871	927
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	117	113	332	341
Duke Energy Carolinas | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	62	76	184	222
Progress Energy
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,179	3,167	8,039	8,334
Revenue from sources other than contracts with customers	18	75	78	224
Total operating revenues	3,197	3,242	8,117	8,558
Progress Energy | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,179	3,167	8,039	8,334
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,550	1,522	3,792	3,879
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	805	843	2,080	2,225
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	245	255	673	708
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	412	429	1,018	1,133
Progress Energy | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	167	118	476	389
Duke Energy Progress
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,612	1,651	4,151	4,446
Revenue from sources other than contracts with customers	14	37	56	113
Total operating revenues	1,626	1,688	4,207	4,559
Duke Energy Progress | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,612	1,651	4,151	4,446
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	616	625	1,578	1,657
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	384	399	1,001	1,044
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	179	189	487	514
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	358	368	877	992
Duke Energy Progress | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	75	70	208	239
Duke Energy Florida
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,567	1,516	3,888	3,888
Revenue from sources other than contracts with customers		32	9	99
Total operating revenues	1,567	1,548	3,897	3,987
Duke Energy Florida | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,567	1,516	3,888	3,888
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	934	897	2,214	2,222
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	421	444	1,079	1,181
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	66	66	186	194
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	54	61	141	141
Duke Energy Florida | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	92	48	268	150
Duke Energy Ohio
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	481	494	1,405	1,454
Revenue from sources other than contracts with customers	(8)	(5)	(11)	(1)
Total operating revenues	473	489	1,394	1,453
Duke Energy Ohio | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	400	413	1,081	1,102
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	213	215	558	563
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	119	127	336	335
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	35	40	103	109
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	10	13	22	36
Duke Energy Ohio | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	23	18	62	59
Duke Energy Ohio | Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	81	81	324	352
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	55	53	214	229
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	20	21	86	96
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3	4	12	14
Duke Energy Ohio | Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3	3	12	13
Duke Energy Indiana
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	762	808	2,067	2,281
Revenue from sources other than contracts with customers	(1)	(1)	3	8
Total operating revenues	761	807	2,070	2,289
Duke Energy Indiana | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	762	808	2,067	2,281
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	289	294	785	825
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	212	225	554	619
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	175	204	502	595
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	64	63	163	176
Duke Energy Indiana | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	22	22	63	66
Piedmont Natural Gas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	144	157	792	924
Revenue from sources other than contracts with customers	18	11	79	32
Total operating revenues	162	168	871	956
Piedmont Natural Gas | Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	144	157	792	924
Piedmont Natural Gas | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	57	59	417	443
Piedmont Natural Gas | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	44	47	222	263
Piedmont Natural Gas | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	22	25	80	91
Piedmont Natural Gas | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Power Generation
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	10	13	27	39
Piedmont Natural Gas | Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 11	$ 13	$ 46	$ 88