Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 6,894	$ 6,658	$ 18,655	$ 17,817
Revenue from sources other than contracts with customers	57	63	204	274
Total operating revenues	6,951	6,721	18,859	18,091
Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6,560	6,378	17,142	16,538
Total operating revenues	6,560	6,371	17,161	16,571
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,955	2,936	7,753	7,451
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,873	1,804	4,805	4,691
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	861	797	2,228	2,148
Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	619	603	1,644	1,535
Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	252	238	712	713
Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	270	216	1,330	1,089
Total operating revenues	266	217	1,323	1,122
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	129	112	747	631
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	78	64	373	308
Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	30	24	110	92
Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	33	16	100	58
Commercial Renewables
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	56	57	163	170
Total operating revenues	117	126	355	378
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	8	7	20	20
Total operating revenues	8	7	20	20
Duke Energy Carolinas
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,120	2,068	5,474	5,423
Revenue from sources other than contracts with customers	(16)	(10)	(44)	(7)
Total operating revenues	2,104	2,058	5,430	5,416
Duke Energy Carolinas | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	2,120	2,068	5,474	5,423
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	892	883	2,368	2,316
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	685	664	1,685	1,720
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	360	342	872	871
Duke Energy Carolinas | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	111	117	341	332
Duke Energy Carolinas | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	72	62	208	184
Progress Energy
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,212	3,179	8,338	8,039
Revenue from sources other than contracts with customers	21	18	79	78
Total operating revenues	3,233	3,197	8,417	8,117
Progress Energy | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,212	3,179	8,338	8,039
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,525	1,550	3,903	3,792
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	826	805	2,170	2,080
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	264	245	700	673
Progress Energy | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	399	412	1,056	1,018
Progress Energy | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	198	167	509	476
Duke Energy Progress
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,656	1,612	4,366	4,151
Revenue from sources other than contracts with customers	11	14	51	56
Total operating revenues	1,667	1,626	4,417	4,207
Duke Energy Progress | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,656	1,612	4,366	4,151
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	619	616	1,657	1,578
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	400	384	1,036	1,001
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	195	179	500	487
Duke Energy Progress | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	324	358	901	877
Duke Energy Progress | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	118	75	272	208
Duke Energy Florida
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,556	1,567	3,972	3,888
Revenue from sources other than contracts with customers	5		15	9
Total operating revenues	1,561	1,567	3,987	3,897
Duke Energy Florida | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,556	1,567	3,972	3,888
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	906	934	2,246	2,214
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	426	421	1,134	1,079
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	69	66	200	186
Duke Energy Florida | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	75	54	155	141
Duke Energy Florida | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	80	92	237	268
Duke Energy Ohio
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	506	481	1,498	1,405
Revenue from sources other than contracts with customers		(8)	(4)	(11)
Total operating revenues	506	473	1,494	1,394
Duke Energy Ohio | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	413	400	1,123	1,081
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	223	213	589	558
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	119	119	329	336
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	35	35	99	103
Duke Energy Ohio | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	19	10	45	22
Duke Energy Ohio | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	17	23	61	62
Duke Energy Ohio | Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	93	81	375	324
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	62	55	241	214
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	24	20	99	86
Duke Energy Ohio | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3	3	14	12
Duke Energy Ohio | Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4	3	21	12
Duke Energy Indiana
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	870	762	2,337	2,067
Revenue from sources other than contracts with customers	16	(1)	29	3
Total operating revenues	886	761	2,366	2,070
Duke Energy Indiana | Electric Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	870	762	2,337	2,067
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	316	289	894	785
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | General
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	240	212	619	554
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	202	175	558	502
Duke Energy Indiana | Electric Utilities and Infrastructure | Electric Utilities and Infrastructure | Wholesale
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	89	64	202	163
Duke Energy Indiana | Electric Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	23	22	64	63
Piedmont
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	182	144	977	792
Revenue from sources other than contracts with customers	13	18	39	79
Total operating revenues	195	162	1,016	871
Piedmont | Gas Utilities and Infrastructure
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	182	144	977	792
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	66	57	505	417
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Commercial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	58	44	273	222
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	26	22	96	80
Piedmont | Gas Utilities and Infrastructure | Gas Utilities and Infrastructure | Power Generation
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	23	10	69	27
Piedmont | Gas Utilities and Infrastructure | Other revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 9	$ 11	$ 34	$ 46