Consolidated Statements of Operations (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Severance Expense Net Of Payments					$ 92
Operating Revenues [Abstract]
Regulated electric	21,550		20,329		15,515
Non-regulated electric, natural gas, and other	1,802		1,916		1,928
Regulated natural gas	573		511		469
Total operating revenues	23,925		22,756		17,912
Operating Expenses [Abstract]
Fuel used in electric generation and purchased power - regulated	7,686		7,108		5,582
Fuel used in electric generation and purchased power - non-regulated	533		540		651
Cost of natural gas and other	248		224		215
Operation, maintenance and other	5,856		5,673		4,787
Depreciation and amortization	3,066		2,668		2,145
Property and other taxes	1,213		1,274		965
Impairment charges	81		399		666
Total operating expenses	18,683		17,886		15,011
Gains (Losses) on Sales of Other Assets and Other, net	16		(16)		10
Operating Income (Loss)	5,258		4,854		2,911
Other Income and Expenses [Abstract]
Equity in earnings of unconsolidated affiliates	130		122		148
Gains on sales of unconsolidated affiliates	17		100		22
Other income and expenses, net	351		262		397
Total other income and expenses	498		484		567
Interest Expense	1,622		1,543		1,244
Income (Loss) From Continuing Operations Before Income Taxes	4,134		3,795		2,234
Income Tax Expense (Benefit) from Continuing Operations	1,669		1,205		623
Net income	1,889		2,676		1,782
Income (Loss) from Continuing Operations	2,465		2,590		1,611
Income (Loss) From Discontinued Operations, net of tax	(576)		86		171
Less: Net Income (Loss) Attributable to Noncontrolling Interests	6		11		14
Net Income (Loss) Attributable to Parent	1,883		2,665		1,768
Net Income (Loss) Available to Parent			2,676		1,780	[1]
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Pension and OPEB adjustments	4	[2]	38	[2]	19	[2]
Net unrealized gain (loss) on cash flow hedges	(26)	[3]	59	[3]	(28)	[3]
Reclassification into earnings from cash flow hedges	7		1		(1)
Unrealized gain (loss) on investments in available for sale securities	3		(4)		14
Other comprehensive income (loss), net of tax	(136)		(99)		(76)
Comprehensive Income (Loss)	1,753		2,577		1,706
Less: Comprehensive Income Attributable to Noncontrolling Interests	14		5		10
Comprehensive income (loss)	1,739		2,572		1,696
Income From Continuing Operations Attributable To Parent Common Shareholders [Abstract]
Basic	$ 3.46		$ 3.64		$ 2.77
Diluted	$ 3.46		$ 3.63		$ 2.77
Income (loss) from discontinued operations attributable To Duke Energy Corporation common shareholders [Abstract]
Basic	$ (0.80)		$ 0.13		$ 0.30
Diluted	$ (0.80)		$ 0.13		$ 0.30
Net income attributable to Duke Energy Corporation common shareholders [Abstract]
Basic	$ 2.66		$ 3.77		$ 3.07
Diluted	$ 2.66		$ 3.76		$ 3.07
Weighted-average shares outstanding [Abstract]
Basic	707		706		574
Diluted	707		706		575
Duke Energy Carolinas [Member]
Operating Revenues [Abstract]
Total operating revenues	7,351		6,954		6,665
Operating Expenses [Abstract]
Fuel used in electric generation and purchased power - regulated	2,133		1,982		1,864
Operation, maintenance and other	1,995		1,868		1,979
Depreciation and amortization	1,009		921		921
Property and other taxes	316		374		365
Impairment charges	3				31
Total operating expenses	5,456		5,145		5,160
Gains (Losses) on Sales of Other Assets and Other, net					12
Operating Income (Loss)	1,895		1,809		1,517
Other Income and Expenses [Abstract]
Other income and expenses, net	172		120		185
Interest Expense	407		359		384
Income (Loss) From Continuing Operations Before Income Taxes	1,660		1,570		1,318
Income Tax Expense (Benefit) from Continuing Operations	588		594		453
Net income	1,072		976
Net Income (Loss) Attributable to Parent	1,072		976		865
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Reclassification into earnings from cash flow hedges	2		1		2
Unrealized gain (loss) on investments in available for sale securities					1
Other comprehensive income (loss), net of tax	2		1		3
Comprehensive income (loss)	1,074		977		868
Progress Energy [Member]
Severance Expense Net Of Payments					38
Operating Revenues [Abstract]
Total operating revenues	10,166		9,533		9,405
Operating Expenses [Abstract]
Fuel used in electric generation and purchased power - regulated	4,195		3,851		4,304
Operation, maintenance and other	2,335		2,247		2,445
Depreciation and amortization	1,128		883		747
Property and other taxes	517		557		570
Impairment charges	(16)		380		200
Total operating expenses	8,159		7,918		8,266
Gains (Losses) on Sales of Other Assets and Other, net	11		3		(2)
Operating Income (Loss)	2,018		1,618		1,137
Other Income and Expenses [Abstract]
Other income and expenses, net	77		94		130
Interest Expense	675		680		740
Income (Loss) From Continuing Operations Before Income Taxes	1,420		1,032		527
Income Tax Expense (Benefit) from Continuing Operations	540		373		172
Net income	874		675		407
Income (Loss) from Continuing Operations	880		659		355
Income (Loss) From Discontinued Operations, net of tax	(6)		16		52
Less: Net Income (Loss) Attributable to Noncontrolling Interests	5		3		7
Net Income (Loss) Attributable to Parent	869		672		400
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Pension and OPEB adjustments	9		9		(2)
Net unrealized gain (loss) on cash flow hedges					(5)
Reclassification into earnings from cash flow hedges	8		(1)		8
Reclassification of cash flow hedges to regulatory assets					97	[4]
Unrealized gain (loss) on investments in available for sale securities	1
Other comprehensive income (loss), net of tax	18		8		98
Comprehensive Income (Loss)	892		683		505
Less: Comprehensive Income Attributable to Noncontrolling Interests	5		3		7
Comprehensive income (loss)	887		680		498
Duke Energy Progress [Member]
Severance Expense Net Of Payments					18
Operating Revenues [Abstract]
Total operating revenues	5,176		4,992		4,706
Operating Expenses [Abstract]
Fuel used in electric generation and purchased power - regulated	2,036		1,925		1,895
Operation, maintenance and other	1,470		1,357		1,494
Depreciation and amortization	582		534		535
Property and other taxes	174		223		219
Impairment charges	(18)		22		54
Total operating expenses	4,244		4,061		4,197
Gains (Losses) on Sales of Other Assets and Other, net	3		1		1
Operating Income (Loss)	935		932		510
Other Income and Expenses [Abstract]
Other income and expenses, net	51		57		79
Interest Expense	234		201		207
Income (Loss) From Continuing Operations Before Income Taxes	752		788		382
Income Tax Expense (Benefit) from Continuing Operations	285		288		110
Net income	467		500		272
Less: Preferred Stock Dividend Requirement					3
Net Income (Loss) Available to Parent	467		500		269
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net unrealized gain (loss) on cash flow hedges					(4)
Reclassification into earnings from cash flow hedges					4
Reclassification of cash flow hedges to regulatory assets					71	[5]
Other comprehensive income (loss), net of tax	0		0		71
Comprehensive income (loss)	467		500		343
Duke Energy Florida [Member]
Severance Expense Net Of Payments					6
Operating Revenues [Abstract]
Total operating revenues	4,975		4,527		4,689
Operating Expenses [Abstract]
Fuel used in electric generation and purchased power - regulated	2,158		1,927		2,409
Operation, maintenance and other	850		898		969
Depreciation and amortization	545		330		192
Property and other taxes	343		327		346
Impairment charges	2		358		146
Total operating expenses	3,898		3,840		4,062
Gains (Losses) on Sales of Other Assets and Other, net	1		1		2
Operating Income (Loss)	1,078		688		629
Other Income and Expenses [Abstract]
Other income and expenses, net	20		30		39
Interest Expense	201		180		255
Income (Loss) From Continuing Operations Before Income Taxes	897		538		413
Income Tax Expense (Benefit) from Continuing Operations	349		213		147
Net income	548		325		266
Less: Preferred Stock Dividend Requirement	0		0		2
Net Income (Loss) Available to Parent	548		325		264
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net unrealized gain (loss) on cash flow hedges	0		(1)		0
Reclassification into earnings from cash flow hedges	1		0		1
Reclassification of cash flow hedges to regulatory assets	0	[6]	0	[6]	26	[6]
Other comprehensive income (loss), net of tax	1		(1)		27
Comprehensive income (loss)	549		324		293
Duke Energy Ohio [Member]
Operating Revenues [Abstract]
Regulated electric	1,316		1,258		1,281
Non-regulated electric, natural gas, and other	19		34		68
Regulated natural gas	578		513		471
Total operating revenues	1,913		1,805		1,820
Operating Expenses [Abstract]
Fuel used in electric generation and purchased power - regulated	459		428		475
Fuel used in electric generation and purchased power - non-regulated	25		41		57
Cost of natural gas and other	185		152		142
Operation, maintenance and other	516		546		586
Depreciation and amortization	214		213		195
Property and other taxes	234		242		205
Impairment charges	94		5		2
Total operating expenses	1,727		1,627		1,662
Gains (Losses) on Sales of Other Assets and Other, net	1		4		1
Operating Income (Loss)	187		182		159
Other Income and Expenses [Abstract]
Other income and expenses, net	10		2		8
Interest Expense	86		74		89
Income (Loss) From Continuing Operations Before Income Taxes	111		110		78
Income Tax Expense (Benefit) from Continuing Operations	43		43		33
Net income	(495)		102		175
Income (Loss) from Continuing Operations	68		67		45
Income (Loss) From Discontinued Operations, net of tax	(563)		35		130
Net Income (Loss) Attributable to Parent	(495)		102		175
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Pension and OPEB adjustments			1		27
Other comprehensive income (loss), net of tax			1		27
Comprehensive income (loss)	(495)		103		202
Duke Energy Indiana [Member]
Operating Revenues [Abstract]
Total operating revenues	3,175		2,926		2,717
Operating Expenses [Abstract]
Fuel used in electric generation and purchased power - regulated	1,259		1,131		1,088
Operation, maintenance and other	670		649		655
Depreciation and amortization	413		342		389
Property and other taxes	128		71		81
Impairment charges	0		0		579
Total operating expenses	2,470		2,193		2,792
Operating Income (Loss)	705		733		(75)
Other Income and Expenses [Abstract]
Other income and expenses, net	22		18		90
Interest Expense	171		170		138
Income (Loss) From Continuing Operations Before Income Taxes	556		581		(123)
Income Tax Expense (Benefit) from Continuing Operations	197		223		(73)
Net income	359		358
Net Income (Loss) Attributable to Parent	359		358		(50)
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Reclassification into earnings from cash flow hedges			(2)		(2)
Other comprehensive income (loss), net of tax			(2)		(2)
Comprehensive income (loss)	$ 359		$ 356		$ (52)

[1] For the year ended December 31, 2012, consolidated net income of $1,782 million includes $2 million attributable to preferred shareholders of subsidiaries. Income attributable to preferred shareholders of subsidiaries is not a component of total equity and is excluded from the table above.

[2] Net of insignificant tax expense in 2014, $17 million tax expense in 2013 and $9 million tax expense in 2012. See Note 21 for additional information.

[3] Net of $13 million tax benefit in 2014, $20 million tax expense in 2013 and $6 million tax expense in 2012.

[4] Net of $62 million tax expense in 2012.

[5] Net of $46 million tax expense in 2012.

[6] Net of $16 million tax expense in 2012.