Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Millions	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] 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 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 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]
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
Beginning member's equity at Dec. 31, 2013											$ 10,350	$ 10,365	$ (14)	$ (1)
Net income (loss)	520			512					512	8					405		404				404	1
Net Income (Loss) Attributable to Parent	512										556	556			404								234		234	250		250		(997)			(997)	200			200
Other comprehensive income (loss), net of tax	45				51	(9)	$ 2		44	1	2		2		5			4		1	5					1			$ 1
Distributions to parent											(251)	(251)
Common stock issuances, including dividend reinvestment and employee benefits, shares		1,000,000
Common stock issuances, including dividend reinvestment and employee benefits	24		24						24
Common stock dividends	(1,107)			(1,107)					(1,107)														(125)		(125)	(124)		(124)		(100)		(100)		(225)			(225)
Distributions to noncontrolling interest in subsidiaries	(9)									(9)					(2)							(2)
Transfer of service company net assets to Duke Energy															(539)		(539)				(539)
Balance at Jun. 30, 2014	40,881	$ 1	39,389	1,768	(256)	(49)	2	(52)	40,803	78					10,733	7,467	3,317	(39)		(15)	10,730	3	5,734	2,159	3,575	4,924	1,762	3,162		4,172	762	4,782	(1,372)	3,914	1	1,384	2,526	3
Balance, in shares at Jun. 30, 2014		707,000,000
Ending member's equity at Jun. 30, 2014											10,657	10,670	(12)	(1)
Balance at Dec. 31, 2014	$ 40,899	$ 1	39,405	2,012	(439)	(59)	3	(48)	40,875	24					$ 11,176	7,467	3,782	(35)	$ 1	(7)	11,208	(32)	$ 5,867	2,159	3,708	$ 5,222	1,762	3,460		$ 4,674	762	4,782	(870)	$ 3,848	1	1,384	2,460	3
Balance, in shares at Dec. 31, 2014	707,000,000	707,000,000													100								160,000,000			100				89,663,086				53,913,701
Beginning member's equity at Dec. 31, 2014											10,924	10,937	(12)	(1)
Net income (loss)	$ 1,414			1,407					1,407	7					$ 480		475				475	5
Net Income (Loss) Attributable to Parent	1,407										557	557			475								$ 268		268	$ 278		278		$ 97			97	$ 176			176
Other comprehensive income (loss), net of tax	(110)				(111)	7	$ (3)	2	(105)	(5)					0			(1)	$ (1)	2														(1)				(1)
Distributions to parent											(100)	(100)
Common stock issuances, including dividend reinvestment and employee benefits, shares		1,000,000
Common stock issuances, including dividend reinvestment and employee benefits	$ 28		28						28
Stock repurchase, Shares	(19,800,000)	(20,000,000)
Stock Repurchase	$ (1,500)		(1,500)						(1,500)
Common stock dividends	(1,115)			(1,115)					(1,115)																	(350)		(350)						(150)			(150)
Distributions to noncontrolling interest in subsidiaries	(7)									(7)					(4)							(4)
Other	8			(10)					(10)	18					2		(2)				(2)	4
Distribution of membership interest of Duke Energy SAM, LLC to parent																														(1,912)		(1,912)
Balance at Jun. 30, 2015	$ 39,617	$ 1	$ 37,933	$ 2,294	$ (550)	$ (52)		$ (46)	$ 39,580	$ 37					$ 11,654	$ 7,467	$ 4,255	$ (36)		$ (5)	$ 11,681	$ (27)	$ 6,135	$ 2,159	$ 3,976	$ 5,150	$ 1,762	$ 3,388		$ 2,859	$ 762	$ 2,870	$ (773)	$ 3,873	$ 1	$ 1,384	$ 2,486	$ 2
Balance, in shares at Jun. 30, 2015	688,000,000	688,000,000													100								160,000,000			100				89,663,086				53,913,701
Ending member's equity at Jun. 30, 2015											$ 11,381	$ 11,394	$ (12)	$ (1)