Organization and Basis of Presentation Organization and Basis of Presentation (Amounts Attributable to Controlling Interests) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Organization And Basis Of Presentation [Line Items]
Income From Continuing Operations	$ 940	$ 891	$ 2,320	$ 2,367
Income From Continuing Operations Attributable to Noncontrolling Interests	3	3	10	11
Income (Loss) from Continuing Operations Attributable to Parent	937	888	2,310	2,356
(Loss) Income From Discontinued Operations, net of tax	(5)	378	29	(578)
Loss From Discontinued Operations Attributable to Noncontrolling Interests, net of tax		(8)		(8)
Income (Loss) From Discontinued Operations Attributable to Duke Energy Corporation, net of tax		386		(570)
Net Income	935	1,269	2,349	1,789
Net Income (Loss) Attributable to Noncontrolling Interests	3	(5)	10	3
Net Income (Loss) Attributable to Parent	932	1,274	2,339	1,786
Progress Energy [Member]
Organization And Basis Of Presentation [Line Items]
Income From Continuing Operations	452	330	933	741
Income From Continuing Operations Attributable to Noncontrolling Interests		1		2
Income (Loss) from Continuing Operations Attributable to Parent		329		739
(Loss) Income From Discontinued Operations, net of tax	(1)		(2)	(6)
Income (Loss) From Discontinued Operations Attributable to Duke Energy Corporation, net of tax		0		(6)
Net Income	451	330	931	735
Net Income (Loss) Attributable to Noncontrolling Interests	3	1	8	2
Net Income (Loss) Attributable to Parent	$ 448	$ 329	$ 923	$ 733