Property, Plant and Equipment (Schedule Of Property, Plant and Equipment) (Details) - USD ($) $ in Millions	2 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Oct. 31, 2016	Dec. 31, 2015	Oct. 31, 2015
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	$ 1,501	$ 1,559	$ 1,501
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	4,184	4,498	4,184
Equipment	1,941	2,122	1,941
Construction in process	6,186	6,995	6,186
Total property, plant and equipment	121,397	127,507	121,397
Generation facilities to be retired, net	529	421	529
Total net property, plant and equipment	82,520	86,391	82,520
Asset Impairment Charges		282	18		$ 106
Capitalized leases	1,355	1,294	1,355
Accumulated amortization on capitalized leases	50	57	50
Capitalized Interest Costs [Abstract]
Capitalized interest		$ 128	100		98
Commercial Renewables [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Asset Impairment Charges			$ 71
Minimum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other, estimated useful life, in years		3 years	5 years
Equipment, estimated useful life, years		3 years	3 years
Maximum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other, estimated useful life, in years		40 years	40 years
Equipment, estimated useful life, years		55 years	38 years
Nuclear Fuel [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Nuclear fuel	3,572	$ 3,680	$ 3,572
Accumulated depreciation and amortization	(1,922)	(2,113)	(1,922)
Variable Interest Entity, Primary Beneficiary [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Total property, plant and equipment	2,591	3,941	2,591
Accumulated depreciation and amortization	(411)	(598)	(411)
Regulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(37,831)	(39,742)	(37,831)
Regulated Operation [Member] | Electric Plant [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	89,864	$ 93,687	$ 89,864
Regulated Operation [Member] | Electric Plant [Member] | Minimum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution, estimated useful life, in years		8 years	8 years
Regulated Operation [Member] | Electric Plant [Member] | Maximum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution, estimated useful life, in years		100 years	100 years
Regulated Operation [Member] | Natural Gas [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	7,738	$ 8,292	$ 7,738
Regulated Operation [Member] | Natural Gas [Member] | Minimum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution, estimated useful life, in years		12 years	12 years
Regulated Operation [Member] | Natural Gas [Member] | Maximum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution, estimated useful life, in years		80 years	67 years
Regulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	1,692	$ 1,936	$ 1,692
Regulated Operation [Member] | Other Buildings And Improvements [Member] | Minimum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other, estimated useful life, in years		15 years	15 years
Regulated Operation [Member] | Other Buildings And Improvements [Member] | Maximum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other, estimated useful life, in years		100 years	100 years
Nonregulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(1,575)	$ (1,795)	$ (1,575)
Nonregulated Operation [Member] | Electric Plant [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	4,298	$ 4,273	$ 4,298
Nonregulated Operation [Member] | Electric Plant [Member] | Minimum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution, estimated useful life, in years		5 years	5 years
Nonregulated Operation [Member] | Electric Plant [Member] | Maximum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution, estimated useful life, in years		30 years	30 years
Nonregulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	421	$ 465	$ 421
Nonregulated Operation [Member] | Other Buildings And Improvements [Member] | Minimum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other, estimated useful life, in years		25 years	25 years
Nonregulated Operation [Member] | Other Buildings And Improvements [Member] | Maximum [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Other, estimated useful life, in years		35 years	35 years
Duke Energy Carolinas [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	432	$ 467	$ 432
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	904	1,032	904
Equipment	358	402	358
Construction in process	2,324	2,614	2,324
Total property, plant and equipment	41,127	42,939	41,127
Total net property, plant and equipment	26,762	27,876	26,762
Asset Impairment Charges			1		1
Capitalized leases	40	81	40
Accumulated amortization on capitalized leases	9	11	9
Capitalized Interest Costs [Abstract]
Capitalized interest		45	38		38
Duke Energy Carolinas [Member] | Nuclear Fuel [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Nuclear fuel	2,092	2,120	2,092
Accumulated depreciation and amortization	(1,192)	(1,283)	(1,192)
Duke Energy Carolinas [Member] | Regulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(14,365)	(15,063)	(14,365)
Duke Energy Carolinas [Member] | Regulated Operation [Member] | Electric Plant [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	34,515	35,657	34,515
Duke Energy Carolinas [Member] | Regulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	502	647	502
Progress Energy [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	735	767	735
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	1,206	1,311	1,206
Equipment	505	555	505
Construction in process	2,708	3,059	2,708
Total property, plant and equipment	44,864	47,323	44,864
Generation facilities to be retired, net	529	421	529
Total net property, plant and equipment	30,181	31,887	30,181
Asset Impairment Charges		156	7		12
Capitalized leases net of accumulated amortization	288	272	288
Accumulated amortization on capitalized leases	99	114	99
Capitalized Interest Costs [Abstract]
Capitalized interest		45	31		24
Progress Energy [Member] | Nuclear Fuel [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Nuclear fuel	1,480	1,560	1,480
Accumulated depreciation and amortization	(730)	(831)	(730)
Progress Energy [Member] | Regulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(15,212)	(15,857)	(15,212)
Progress Energy [Member] | Regulated Operation [Member] | Electric Plant [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	37,596	39,419	37,596
Progress Energy [Member] | Regulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	634	652	634
Duke Energy Progress [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	393	424	393
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	863	931	863
Equipment	378	416	378
Construction in process	1,329	1,434	1,329
Total property, plant and equipment	28,419	29,583	28,419
Generation facilities to be retired, net	529	421	529
Total net property, plant and equipment	18,387	19,101	18,387
Asset Impairment Charges		19	1		5
Capitalized leases net of accumulated amortization	142	139	142
Accumulated amortization on capitalized leases	9	11	9
Capitalized Interest Costs [Abstract]
Capitalized interest		21	17		20
Duke Energy Progress [Member] | Nuclear Fuel [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Nuclear fuel	1,480	1,560	1,480
Accumulated depreciation and amortization	(730)	(831)	(730)
Duke Energy Progress [Member] | Regulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(10,561)	(10,903)	(10,561)
Duke Energy Progress [Member] | Regulated Operation [Member] | Electric Plant [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	23,683	24,502	23,683
Duke Energy Progress [Member] | Regulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	293	316	293
Duke Energy Florida [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	342	343	342
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	332	370	332
Equipment	127	139	127
Construction in process	1,379	1,625	1,379
Total property, plant and equipment	16,434	17,730	16,434
Total net property, plant and equipment	11,790	12,783	11,790
Asset Impairment Charges		138	6		7
Capitalized leases net of accumulated amortization	146	133	146
Accumulated amortization on capitalized leases	90	103	90
Capitalized Interest Costs [Abstract]
Capitalized interest		24	14		4
Duke Energy Florida [Member] | Regulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(4,644)	(4,947)	(4,644)
Duke Energy Florida [Member] | Regulated Operation [Member] | Electric Plant [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	13,913	14,917	13,913
Duke Energy Florida [Member] | Regulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	341	336	341
Duke Energy Ohio [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	150	134	150
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	172	228	172
Equipment	338	348	338
Construction in process	206	350	206
Total property, plant and equipment	8,126	8,732	8,126
Total net property, plant and equipment	5,547	6,041	5,547
Asset Impairment Charges		1
Capitalized leases	81	80	81
Accumulated amortization on capitalized leases	19	21	19
Capitalized Interest Costs [Abstract]
Capitalized interest		10	8		10
Duke Energy Ohio [Member] | Regulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(2,579)	(2,691)	(2,579)
Duke Energy Ohio [Member] | Regulated Operation [Member] | Electric Plant [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	4,593	4,870	4,593
Duke Energy Ohio [Member] | Regulated Operation [Member] | Natural Gas [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	2,456	2,559	2,456
Duke Energy Ohio [Member] | Regulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	211	243	211
Duke Energy Indiana [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	106	111	106
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	226	271	226
Equipment	156	169	156
Construction in process	396	416	396
Total property, plant and equipment	14,241	14,948	14,241
Total net property, plant and equipment	9,924	10,286	9,924
Asset Impairment Charges		18	8		88
Capitalized leases	35	35	35
Accumulated amortization on capitalized leases	8	9	8
Capitalized Interest Costs [Abstract]
Capitalized interest		9	7		$ 6
Duke Energy Indiana [Member] | Regulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(4,317)	(4,662)	(4,317)
Duke Energy Indiana [Member] | Regulated Operation [Member] | Electric Plant [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	13,160	13,741	13,160
Duke Energy Indiana [Member] | Regulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	197	240	197
Piedmont Natural Gas [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Land	39	41	39
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	235	300	235
Equipment	260	266	260
Construction in process	210	231	210
Total property, plant and equipment	6,174	6,725	6,174
Total net property, plant and equipment	4,814	5,246	4,814
Asset Impairment Charges		7
Capitalized Interest Costs [Abstract]
Capitalized interest	2	12		$ 12		$ 11
Piedmont Natural Gas [Member] | Regulated Operation [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Accumulated depreciation and amortization	(1,360)	(1,479)	(1,360)
Piedmont Natural Gas [Member] | Regulated Operation [Member] | Natural Gas [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Plant - transmission and distribution	5,282	5,733	5,282
Piedmont Natural Gas [Member] | Regulated Operation [Member] | Other Buildings And Improvements [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment	$ 148	154	$ 148
Property, Plant and Equipment [Member] | Commercial Renewables [Member]
Public Utilities, Property, Plant and Equipment, Net [Abstract]
Asset Impairment Charges		$ 58