Condensed Consolidated Statements of Changes in Equity (USD $) In Millions, except Share data, unless otherwise specified	Total	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Foreign Currency Translation Adjustments [Member]	Net Gains (Losses) on Cash Flow Hedges [Member]	Net Gains (Losses) on Available for Sale Securities [Member]	Pension and OPEB Related Adjustments [Member]	Common Stockholders' Equity [Member]	Noncontrolling Interest [Member]	Duke Energy Carolinas [Member]	Duke Energy Carolinas [Member] Members Equity [Member]	Duke Energy Carolinas [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Duke Energy Carolinas [Member] Net Gains (Losses) on Available for Sale Securities [Member]	Progress Energy [Member]	Progress Energy [Member] Common Stock [Member]	Progress Energy [Member] Additional Paid In Capital [Member]	Progress Energy [Member] Retained Earnings [Member]	Progress Energy [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Progress Energy [Member] Net Gains (Losses) on Available for Sale Securities [Member]	Progress Energy [Member] Pension and OPEB Related Adjustments [Member]	Progress Energy [Member] Common Stockholders' Equity [Member]	Progress Energy [Member] Noncontrolling Interest [Member]	Duke Energy Progress [Member]	Duke Energy Progress [Member] Common Stock [Member]	Duke Energy Progress [Member] Retained Earnings [Member]	Duke Energy Florida [Member]	Duke Energy Florida [Member] Common Stock [Member]	Duke Energy Florida [Member] Retained Earnings [Member]	Duke Energy Florida [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Duke Energy Florida [Member] Pension and OPEB Related Adjustments [Member]	Duke Energy Ohio [Member]	Duke Energy Ohio [Member] Common Stock [Member]	Duke Energy Ohio [Member] Additional Paid In Capital [Member]	Duke Energy Ohio [Member] Retained Earnings [Member]	Duke Energy Ohio [Member] Pension and OPEB Related Adjustments [Member]	Duke Energy Indiana [Member]	Duke Energy Indiana [Member] Common Stock [Member]	Duke Energy Indiana [Member] Additional Paid In Capital [Member]	Duke Energy Indiana [Member] Retained Earnings [Member]	Duke Energy Indiana [Member] Net Gains (Losses) on Cash Flow Hedges [Member]
Beginning member's equity at Dec. 31, 2012											$ 9,872	$ 9,888	$ (15)	$ (1)
Balance at Dec. 31, 2012	40,941	1	39,279	1,889	(116)	(100)		(90)	40,863	78					10,185		7,465	2,783	(42)		(25)	10,181	4	5,127	2,159	2,968	4,799	1,762	3,037			5,166	762	4,882	(477)	(1)	3,708	1	1,384	2,318	5
Balance, in shares at Dec. 31, 2012		704,000,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,984			1,977					1,977						479			477				477	2
Net Income (Loss) Attributable to Noncontrolling Interest	7														2
Net Income (Loss) Attributable to Parent	1,977										767	767			477									362		362	250		250			96			96		276			276
Other comprehensive income (loss), net of tax	(78)				(133)	56	(2)	5	(74)	(4)	1		1		8				3		5	8					(1)				(1)	1				1	(2)				(2)
Common stock issuances, including dividend reinvestment and employee benefits	38		38						38
Common stock issuances, including dividend reinvestment and employee benefits, shares		2,000,000
Common stock dividends	(1,636)			(1,636)					(1,636)																		(225)		(225)								(125)			(125)
Distributions to parent											(500)	(500)
Premium on the redemption of preferred stock of subsidiaries	(3)			(3)					(3)						(3)			(3)				(3)		(2)		(2)	(1)		(1)
Changes in noncontrolling interest in subsidiaries	(9)									(9)
Distributions to noncontrolling interest in subsidiaries															(2)								(2)
Ending member's equity at Sep. 30, 2013											10,140	10,155	(14)	(1)
Balance at Sep. 30, 2013	41,237	1	39,317	2,227	(249)	(44)	(2)	(85)	41,165	72					10,667		7,465	3,257	(39)		(20)	10,663	4	5,487	2,159	3,328	4,822	1,762	3,061		(1)	5,263	762	4,882	(381)		3,857	1	1,384	2,469	3
Balance, in shares at Sep. 30, 2013		706,000,000
Beginning member's equity at Jun. 30, 2013
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,008														342
Net Income (Loss) Attributable to Noncontrolling Interest	4														1
Net Income (Loss) Attributable to Parent	1,004										342				341									175			197					59					104
Other comprehensive income (loss), net of tax	(4)														4												(1)
Ending member's equity at Sep. 30, 2013											10,140
Balance at Sep. 30, 2013	41,237														10,667		7,465							5,487			4,822	1,762				5,263	762	4,882			3,857
Beginning member's equity at Dec. 31, 2013											10,350	10,365	(14)	(1)
Balance at Dec. 31, 2013	41,408	1	39,365	2,363	(307)	(40)		(52)	41,330	78					10,864		7,467	3,452	(43)		(16)	10,860	4	5,625	2,159	3,466	4,797	1,762	3,036	(1)		5,269	762	4,882	(375)		3,939	1	1,384	2,551	3
Balance, in shares at Dec. 31, 2013	706,000,000	706,000,000													100									160,000,000			100					89,663,086					53,913,701
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,789			1,786					1,786						735			733				733	2
Net Income (Loss) Attributable to Noncontrolling Interest	3									3					2
Net Income (Loss) Attributable to Parent	1,786										933	933			733									391		391	455					(558)			(558)		301			301
Other comprehensive income (loss), net of tax	(52)				(55)	(5)	2	1	(57)	5	2		2		8				5	1	2	8					1			1
Common stock issuances, including dividend reinvestment and employee benefits	23		23						23
Common stock issuances, including dividend reinvestment and employee benefits, shares		1,000,000
Common stock dividends	(1,670)			(1,670)					(1,670)															(224)		(224)	(124)		(124)			(100)		(100)			(451)			(451)
Distributions to parent											(376)	(376)
Distributions to noncontrolling interest in subsidiaries	(45)									(45)					(37)								(37)
Transfer of service company net assets to Duke Energy															(538)			(538)				(538)
Ending member's equity at Sep. 30, 2014											10,909	10,922	(12)	(1)
Balance at Sep. 30, 2014	41,453	1	39,388	2,479	(362)	(45)	2	(51)	41,412	41					11,032		7,467	3,647	(38)	1	(14)	11,063	(31)	5,792	2,159	3,633	5,129	1,762	3,367			4,611	762	4,782	(933)		3,789	1	1,384	2,401	3
Balance, in shares at Sep. 30, 2014	707,000,000	707,000,000													100									160,000,000			100					89,663,086					53,913,701
Beginning member's equity at Jun. 30, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	1,269														330
Net Income (Loss) Attributable to Noncontrolling Interest	(5)														1
Net Income (Loss) Attributable to Parent	1,274										377				329									157			205					439					101
Other comprehensive income (loss), net of tax	(97)														3												0
Ending member's equity at Sep. 30, 2014											10,909
Balance at Sep. 30, 2014	$ 41,453														$ 11,032		$ 7,467							$ 5,792			$ 5,129	$ 1,762				$ 4,611	$ 762				$ 3,789
Balance, in shares at Sep. 30, 2014	707,000,000														100									160,000,000			100					89,663,086					53,913,701