Condensed Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating Revenues
Regulated electric	$ 5,285	$ 5,284
Regulated natural gas	728	700
Nonregulated electric and other	150	151
Total operating revenues	6,163	6,135
Operating Expenses
Operation, maintenance and other	1,419	1,464
Depreciation and amortization	1,089	967
Property and other taxes	343	316
Impairment charges		43
Total operating expenses	4,787	4,779
Losses on Sales of Other Assets and Other, net	(3)	(100)
Operating Income	1,373	1,256
Other Income and Expenses
Equity in earnings (losses) of unconsolidated affiliates	43	(24)
Other income and expenses, net	115	86
Total other income and expenses	158	62
Interest Expense	543	515
Income Before Income Taxes	988	803
Income Tax Expense	95	181
Net Income	893	622
Less: Net (Loss) Income Attributable to Noncontrolling Interests	(7)	2
Net Income Attributable to Duke Energy Corporation	900	620
Other Comprehensive Income (Loss), net of tax
Pension and OPEB adjustments		1
Net unrealized (losses) gains on cash flow hedges	(17)	12
Reclassification into earnings from cash flow hedges	1	1
Unrealized gains (losses) on available-for-sale securities	4	(3)
Other Comprehensive (Loss) Income, net of tax	(12)	11
Comprehensive Income	881	633
Less: Comprehensive (Loss) Income Attributable to Noncontrolling Interests	(7)	2
Comprehensive Income Attributable to Duke Energy Corporation	$ 888	$ 631
Net income attributable to Duke Energy Corporation common stockholders
Basic and Diluted (in usd per share)	$ 1.24	$ 0.88
Weighted average shares outstanding
Basic and Diluted (in shares)	727	701
Duke Energy Carolinas [Member]
Operating Revenues
Total operating revenues	$ 1,744	$ 1,763
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	472	473
Operation, maintenance and other	440	451
Depreciation and amortization	317	272
Property and other taxes	80	72
Impairment charges		13
Total operating expenses	1,309	1,281
Operating Income	435	482
Other Income and Expenses
Total other income and expenses	31	39
Interest Expense	110	107
Income Before Income Taxes	356	414
Income Tax Expense	63	91
Net Income Attributable to Duke Energy Corporation	293	323
Other Comprehensive Income (Loss), net of tax
Reclassification into earnings from cash flow hedges	0	1
Other Comprehensive (Loss) Income, net of tax		1
Comprehensive Income Attributable to Duke Energy Corporation	293	324
Progress Energy [Member]
Operating Revenues
Total operating revenues	2,572	2,576
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	925	976
Operation, maintenance and other	567	623
Depreciation and amortization	455	384
Property and other taxes	137	123
Impairment charges		29
Total operating expenses	2,084	2,135
Losses on Sales of Other Assets and Other, net		6
Operating Income	488	447
Other Income and Expenses
Total other income and expenses	31	35
Interest Expense	219	209
Income Before Income Taxes	300	273
Income Tax Expense	52	36
Net Income	248	237
Less: Net (Loss) Income Attributable to Noncontrolling Interests	(1)	2
Net Income Attributable to Duke Energy Corporation	249	235
Other Comprehensive Income (Loss), net of tax
Pension and OPEB adjustments	1	0
Net unrealized (losses) gains on cash flow hedges	2	2
Other Comprehensive (Loss) Income, net of tax	3	2
Comprehensive Income	251	239
Less: Comprehensive (Loss) Income Attributable to Noncontrolling Interests	(1)	2
Comprehensive Income Attributable to Duke Energy Corporation	252	237
Duke Energy Progress [Member]
Operating Revenues
Total operating revenues	1,484	1,460
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	515	509
Operation, maintenance and other	335	381
Depreciation and amortization	290	235
Property and other taxes	44	35
Impairment charges		32
Total operating expenses	1,184	1,192
Losses on Sales of Other Assets and Other, net		1
Operating Income	300	269
Other Income and Expenses
Total other income and expenses	24	18
Interest Expense	77	81
Income Before Income Taxes	247	206
Income Tax Expense	44	29
Net Income Attributable to Duke Energy Corporation	203	177
Other Comprehensive Income (Loss), net of tax
Comprehensive Income Attributable to Duke Energy Corporation	203	177
Duke Energy Florida [Member]
Operating Revenues
Total operating revenues	1,086	1,115
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	410	467
Operation, maintenance and other	230	237
Depreciation and amortization	165	150
Property and other taxes	93	88
Total operating expenses	898	942
Operating Income	188	173
Other Income and Expenses
Total other income and expenses	13	21
Interest Expense	82	71
Income Before Income Taxes	119	123
Income Tax Expense	23	20
Net Income Attributable to Duke Energy Corporation	96	103
Other Comprehensive Income (Loss), net of tax
Unrealized gains (losses) on available-for-sale securities	1
Other Comprehensive (Loss) Income, net of tax	1	0
Comprehensive Income Attributable to Duke Energy Corporation	97	103
Duke Energy Ohio [Member]
Operating Revenues
Regulated electric	355	336
Regulated natural gas	176	174
Nonregulated electric and other		14
Total operating revenues	531	524
Operating Expenses
Operation, maintenance and other	132	131
Depreciation and amortization	64	70
Property and other taxes	84	77
Total operating expenses	427	439
Losses on Sales of Other Assets and Other, net		(106)
Operating Income	104	(21)
Other Income and Expenses
Total other income and expenses	9	6
Interest Expense	30	22
Income Before Income Taxes	83	(37)
Income Tax Expense	14	(12)
Net Income Attributable to Duke Energy Corporation	69	(25)
Other Comprehensive Income (Loss), net of tax
Comprehensive Income Attributable to Duke Energy Corporation	69	(25)
Duke Energy Indiana [Member]
Operating Revenues
Total operating revenues	768	731
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	257	232
Operation, maintenance and other	189	181
Depreciation and amortization	131	130
Property and other taxes	19	20
Total operating expenses	596	563
Losses on Sales of Other Assets and Other, net	(3)
Operating Income	169	168
Other Income and Expenses
Total other income and expenses	19	7
Interest Expense	43	40
Income Before Income Taxes	145	135
Income Tax Expense	35	35
Net Income Attributable to Duke Energy Corporation	110	100
Other Comprehensive Income (Loss), net of tax
Comprehensive Income Attributable to Duke Energy Corporation	110	100
Piedmont Natural Gas [Member]
Operating Revenues
Total operating revenues	579	553
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	273	259
Operation, maintenance and other	80	82
Depreciation and amortization	42	39
Property and other taxes	12	12
Total operating expenses	407	392
Operating Income	172	161
Other Income and Expenses
Equity in earnings (losses) of unconsolidated affiliates	2	2
Other income and expenses, net	4	3
Total other income and expenses	6	5
Interest Expense	22	21
Income Before Income Taxes	156	145
Income Tax Expense	34	35
Net Income Attributable to Duke Energy Corporation	122	110
Other Comprehensive Income (Loss), net of tax
Comprehensive Income Attributable to Duke Energy Corporation	122	110
Electricity, US Regulated [Member] | Duke Energy Ohio [Member]
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	93	92
Electricity, Nonregulated [Member] | Duke Energy Ohio [Member]
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas		15
Electricity [Member]
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	1,609	1,676
Natural Gas [Member]
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	327	313
Natural Gas [Member] | Duke Energy Ohio [Member]
Operating Expenses
Fuel used in electric generation and purchased power/Cost of natural gas	$ 54	$ 54