Condensed Consolidated Statements of Equity (Unaudited) (USD $) In Millions, except Share data, unless otherwise specified	Total	Common Stock [Member]	Additional Paid In Capital [Member]	Retained Earnings [Member]	Foreign Currency Adjustments [Member]	Net Gains (Losses) on Cash Flow Hedges [Member]	Net Gains (Losses) on Available for Sale Securities [Member]	Pension And OPEB Related Adjustments To AOCI [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] Pension And OPEB Related Adjustments To AOCI [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 Progress [Member] Net Gains (Losses) on Cash Flow Hedges [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 Ohio [Member] Pension And OPEB Related Adjustments To AOCI [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, 2011	$ 22,865	$ 1	$ 21,132	$ 1,873	$ (45)	$ (71)	$ (9)	$ (109)	$ 22,772	$ 93	$ 9,454	$ 9,473	$ (17)	$ (2)	$ 10,025	$ 7,418	$ 16	$ 2,752	$ (142)	$ (23)	$ 10,021		$ 4	$ 5,088	$ 2,148	$ 3,011	$ (71)	$ 4,675	$ 1,757	$ 2,945	$ (27)	$ 5,167	$ 762	$ 5,085	$ (652)	$ (28)	$ 3,734	$ 1	$ 1,358	$ 2,368	$ 7
Balance (in shares) at Dec. 31, 2011	445,000,000
Net income	747										477	477			216									83		83		211		211		119			119		(90)			(90)
Net income				739					739	8					214			213			213	[1]	1
Other comprehensive income (loss), net of tax	(90)				(83)	(15)	6	6	(86)	(4)	2		2		1				0	1	1			(1)			(1)				0	1				1	(1)				(1)
Common stock issuances, including dividend reinvestment and employee benefits (in shares)	1,000,000
Common stock issuances, including dividend reinvestment and employee benefits	8		8						8						31	25	6				31
Stock-based compensation expense																								11	11			5	5
Common stock dividends	(1,014)			(1,014)					(1,014)						(369)			(369)			(369)
Dividends paid to parent																								(310)		(310)		(170)		(170)
Preferred stock dividends at stated rates																								(1)		(1)		(1)		(1)
Transfer of Vermillion Generating Station																																28		(28)			26		26
Distributions to noncontrolling interests															(2)								(2)
Tax dividend																								(3)		(3)		(2)		(2)
Notes To Reconciliation Of Total Equity [Details]
Net income attributable to preferred shareholders of subsidiaries excluded from reconciliation of total equity															2
Balance at Jun. 30, 2012	22,516	1	21,140	1,598	(128)	(86)	(3)	(103)	22,419	97	9,933	9,950	(15)	(2)	9,900	7,443	22	2,596	(142)	(22)	9,897		3	4,867	2,159	2,780	(72)	4,718	1,762	2,983	(27)	5,259	762	5,057	(533)	(27)	3,669	1	1,384	2,278	6
Balance (in shares) at Jun. 30, 2012	446,000,000
Beginning Member's Equity at Mar. 31, 2012
Net income	448										211				64									31				83				45					77
Other comprehensive income (loss), net of tax	(150)														(4)									(6)
Balance at Jun. 30, 2012	22,516	1									9,933			(2)	9,900									4,867				4,718				5,259	762				3,669	1
Balance (in shares) at Jun. 30, 2012	446,000,000
Balance at Dec. 31, 2012	40,941	1	39,279	1,889	(116)	(100)		(90)	40,863	78			(15)	(1)	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														100									160,000,000				100				89,663,086					59,913,701
Beginning Member's Equity at Dec. 31, 2012											9,872	9,888
Net income	976										425	425			137									187		187		53		53		37			37		172			172
Net income				973					973	3					137			136			136		1
Other comprehensive income (loss), net of tax	(74)				(125)	54	(4)	5	(70)	(4)					4				3	1	4			0								1				1	(1)				(1)
Common stock issuances, including dividend reinvestment and employee benefits (in shares)	2,000,000
Common stock issuances, including dividend reinvestment and employee benefits	5		5						5
Common stock dividends	(1,636)			(1,636)					(1,636)
Dividends paid to parent											(249)	(249)																(225)		(225)
Premium on the redemption of preferred stock of subsidiaries	(3)			(3)					(3)						(3)			(3)			(3)			(2)		(2)		(1)		(1)
Transfer of Vermillion Generating Station																																0					0
Distributions to noncontrolling interests	(8)									(8)					(2)								(2)
Notes To Reconciliation Of Total Equity [Details]
Net income attributable to preferred shareholders of subsidiaries excluded from reconciliation of total equity															0
Balance at Jun. 30, 2013	40,201	1	39,284	1,223	(241)	(46)	(4)	(85)	40,132	69			(15)	(1)	10,321		7,465	2,916	(39)	(24)	10,318		3	5,312	2,159	3,153		4,626	1,762	2,864		5,204	762	4,882	(440)		3,879	1	1,384	2,490	4
Balance (in shares) at Jun. 30, 2013	706,000,000														100									160,000,000				100				89,663,086					59,913,701
Ending Member's Equity at Jun. 30, 2013											10,048	10,064
Beginning Member's Equity at Mar. 31, 2013
Net income	342										181				(17)									77				(57)				58					82
Other comprehensive income (loss), net of tax	(91)														2									0
Balance at Jun. 30, 2013	40,201	1											(15)	(1)	10,321		7,465							5,312	2,159			4,626	1,762			5,204	762	4,882			3,879	1	1,384
Balance (in shares) at Jun. 30, 2013	706,000,000														100									160,000,000				100				89,663,086					59,913,701
Ending Member's Equity at Jun. 30, 2013											$ 10,048

[1] For the six months ended June 30, 2012, consolidated net income of $216 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.