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 Unrealized Gains (Losses) on Available for Sale Securities [Member]	Pension and OPEB 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]	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 Unrealized Gains (Losses) on Available for Sale Securities [Member]	Progress Energy [Member] Pension and OPEB Adjustments [Member]	Progress Energy [Member] Common Stockholders' Equity [Member]	Progress Energy [Member] Noncontrolling Interest [Member]	Duke Energy Progress [Member]	Duke Energy Florida [Member]	Duke Energy Florida [Member] Members Equity [Member]	Duke Energy Florida [Member] Net Unrealized Gains (Losses) on Available for Sale Securities [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] Members Equity [Member]	Duke Energy Indiana [Member] Net Gains (Losses) on Cash Flow Hedges [Member]	Piedmont Natural Gas [Member]	Piedmont Natural Gas [Member] Common Stock [Member]	Piedmont Natural Gas [Member] Retained Earnings [Member]	Piedmont Natural Gas [Member] Net Gains (Losses) on Cash Flow Hedges [Member]
Beginning Balance at Dec. 31, 2015	$ 39,771		$ 1	$ 37,968	$ 2,564		$ (692)	$ (50)	$ (3)	$ (61)	$ 39,727		$ 44				$ 12,853	$ 8,092	$ 4,831	$ (31)		$ (17)	$ 12,875	$ (22)
Beginning Balance, in shares at Dec. 31, 2015			688,000,000
Beginning Balance (member's equity) at Dec. 31, 2015														$ 11,606	$ 11,617	$ (11)									$ 7,059	$ 5,121	$ 5,121
Beginning Balance (parent) at Dec. 31, 2015																													$ 2,784	$ 762	$ 2,720	$ (698)	$ 3,836	$ 1	$ 1,384	$ 2,450		$ 1	$ 1,458	$ 728	$ 731	$ (1)
Net income	699				694						694		5				212		209				209	3
Net income (attributable to parent)	694													271	271		209								137	110	110		59			59	95				$ 95		103		103
Other comprehensive income (loss)	41						48	(12)	4		40		1	1		1	3			1	$ 1	1	3			1		$ 1					(1)					$ (1)
Common stock issuances, including dividend reinvestment and employee benefits, shares			1,000,000
Common stock issuances, including dividend reinvestment and employee benefits	1			1							1																												7	7
Common stock dividends	(570)				(570)						(570)																												(27)		(27)
Distributions to parent														(600)	(600)
Distributions to noncontrolling interest in subsidiaries	(1)												(1)				(1)							(1)
Other																																		$ (1)	$ (1,384)	$ (2,450)	3,835
Ending Balance at Mar. 31, 2016	39,941		$ 1	37,969	2,688		$ (644)	(62)	1	(61)	39,892		49				13,067	8,092	5,040	(30)	1	(16)	13,087	(20)
Ending Balance, in shares at Mar. 31, 2016			689,000,000
Ending Balance (member's equity) at Mar. 31, 2016														11,278	11,288	(10)									7,196	5,232	5,231	1					3,930				3,930
Ending Balance (parent) at Mar. 31, 2016																													$ 2,843	762	2,720	(639)							$ 1,541	735	807	$ (1)
Beginning Balance at Dec. 31, 2016	$ 41,041		$ 1	38,741	2,384			(20)	(1)	(72)	41,033		8				$ 11,807	8,094	3,764	(23)	1	(16)	11,820	(13)
Beginning Balance, in shares at Dec. 31, 2016	700,000,000		700,000,000														100												89,663,086										100
Beginning Balance (member's equity) at Dec. 31, 2016														10,772	10,781	(9)									7,358	4,900	4,899	1					4,067				4,067
Beginning Balance (parent) at Dec. 31, 2016	$ 41,033																$ 11,820												$ 2,996	762	2,695	(461)							$ 1,672	860	812
Net income	717				716						716		1				201		199				199	2
Net income (attributable to parent)	716													270	270		199								147	90	90		$ 42			42	91				91		$ 95		95
Other comprehensive income (loss)	8							3	4	1	8						3			1	1	1	3			1		1
Common stock issuances, including dividend reinvestment and employee benefits	1			1							1
Common stock dividends	(600)				(600)						(600)
Distributions to parent														(175)	(175)
Distributions to noncontrolling interest in subsidiaries	(2)												(2)
Other	21	[1]			21	[1]					21	[1]					1							1
Ending Balance at Mar. 31, 2017	$ 41,186		$ 1	$ 38,742	$ 2,521			$ (17)	$ 3	$ (71)	$ 41,179		$ 7				$ 12,012	$ 8,094	$ 3,963	$ (22)	$ 2	$ (15)	$ 12,022	$ (10)
Ending Balance, in shares at Mar. 31, 2017	700,000,000		700,000,000														100												89,663,086										100
Ending Balance (member's equity) at Mar. 31, 2017														$ 10,867	$ 10,876	$ (9)									$ 7,505	$ 4,991	$ 4,989	$ 2					$ 4,158				$ 4,158
Ending Balance (parent) at Mar. 31, 2017	$ 41,179																$ 12,022												$ 3,038	$ 762	$ 2,695	$ (419)							$ 1,767	$ 860	$ 907

[1] Cumulative-effect adjustment due to implementation of a new accounting standard related to stock-based compensation and the associated income taxes. See Note 1 for more information.