Income Taxes (Components of Income Tax Expense) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current federal taxes	$ (123)		$ (46)		$ (37)
Current state taxes	(37)		35		21
Current foreign taxes	151		133		164
Total current income taxes	(9)		122		148
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred federal taxes	1,129		513		526
Deferred state taxes	142		64		56
Deferred foreign taxes	14		20		32
Total deferred income taxes	1,285	[1]	597	[2]	614	[3]
Investment tax credit amortization	(15)		(14)		(10)
Income tax expense (benefit) from continuing operations	1,261		705		752
Tax expense from discontinued operations	(27)		24		0
Total income tax expense included in Consolidated Statements of Operations	1,234		729		752
Net operating loss carry forward	837		1,127		274
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Domestic	3,320		1,827		1,780
Foreign	600		624		685
Total income (loss) from continuing operations before income taxes	3,920		2,451		2,465
Duke Energy Carolinas [Member]
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current federal taxes	49		(1)		(122)
Current state taxes	11		(25)		30
Total current income taxes	60		(26)		(92)
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred federal taxes	464		408		531
Deferred state taxes	75		77		40
Total deferred income taxes	539		485	[2]	571	[3]
Investment tax credit amortization	(5)		(6)		(7)
Income tax expense (benefit) from continuing operations	594		453		472
Total income tax expense included in Consolidated Statements of Operations	594		453		472
Net operating loss carry forward	0		245		79
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income (loss) from continuing operations before income taxes	1,570		1,318		1,306
Progress Energy [Member]
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current federal taxes	(221)		(88)		(91)
Current state taxes	(37)		2		29
Total current income taxes	(258)		(86)		(62)
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred federal taxes	555		226		365
Deferred state taxes	84		40		27
Total deferred income taxes	639	[1]	266	[2]	392	[3]
Investment tax credit amortization	(8)		(8)		(7)
Income tax expense (benefit) from continuing operations	373		172		323
Tax expense from discontinued operations	(26)		29		(3)
Total income tax expense included in Consolidated Statements of Operations	347		201		320
Net operating loss carry forward	458		357		213
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income (loss) from continuing operations before income taxes	1,032		527		910
Duke Energy Progress [Member]
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current federal taxes	(70)		(48)		(27)
Current state taxes	(10)		(6)		21
Total current income taxes	(80)		(54)		(6)
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred federal taxes	316		162		262
Deferred state taxes	59		9		6
Total deferred income taxes	375	[1]	171	[2]	268	[3]
Investment tax credit amortization	(7)		(7)		(6)
Income tax expense (benefit) from continuing operations	288		110		256
Total income tax expense included in Consolidated Statements of Operations	288		110		256
Net operating loss carry forward	64		257		54
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income (loss) from continuing operations before income taxes	788		382		772
Duke Energy Florida [Member]
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current federal taxes	(143)		6		(60)
Current state taxes	(13)		0		5
Total current income taxes	(156)		6		(55)
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred federal taxes	326		121		214
Deferred state taxes	44		21		22
Total deferred income taxes	370	[1]	142	[2]	236	[3]
Investment tax credit amortization	(1)		(1)		(1)
Income tax expense (benefit) from continuing operations	213		147		180
Total income tax expense included in Consolidated Statements of Operations	213		147		180
Net operating loss carry forward	301		25		41
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income (loss) from continuing operations before income taxes	538		413		494
Duke Energy Ohio [Member]
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current federal taxes	(21)		26		(95)
Current state taxes	(2)		11		1
Total current income taxes	(23)		37		(94)
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred federal taxes	93		72		194
Deferred state taxes	5		(9)		(2)
Total deferred income taxes	98	[1]	63	[2]	192	[3]
Investment tax credit amortization	0		(2)		(2)
Income tax expense (benefit) from continuing operations	75		98		96
Total income tax expense included in Consolidated Statements of Operations	75		98		96
Net operating loss carry forward	29		99		47
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income (loss) from continuing operations before income taxes	177		273		290
Duke Energy Indiana [Member]
Current Income Tax Expense (Benefit), Continuing Operations [Abstract]
Current federal taxes	(88)		(27)		95
Current state taxes	7		27		42
Total current income taxes	(81)		0		137
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Deferred federal taxes	276		(47)		(38)
Deferred state taxes	29		(25)		(23)
Total deferred income taxes	305	[1]	(72)	[2]	(61)
Investment tax credit amortization	(1)		(1)		(2)
Income tax expense (benefit) from continuing operations	223		(73)		74
Total income tax expense included in Consolidated Statements of Operations	223		(73)		74
Net operating loss carry forward	179		205
Duke Energy Income from Continuing Operations Before Income Taxes [Abstract]
Total income (loss) from continuing operations before income taxes	$ 581		$ (123)		$ 242

[1] Includes benefits of net operating loss (NOL) carryforwards of $837 million at Duke Energy, $458 million at Progress Energy, $64 million at Duke Energy Progress, $301 million at Duke Energy Florida, $29 million at Duke Energy Ohio and $179 million at Duke Energy Indiana.

[2] Includes benefits of NOL carryforwards of $1,127 million at Duke Energy, $245 million at Duke Energy Carolinas, $357 million at Progress Energy, $257 million at Duke Energy Progress, $25 million at Duke Energy Florida, $99 million at Duke Energy Ohio and $205 million at Duke Energy Indiana.

[3] Includes benefits of NOL carryforwards of $274 million at Duke Energy, $79 million at Duke Energy Carolinas, $213 million at Progress Energy, $54 million at Duke Energy Progress, $41 million at Duke Energy Florida and $47 million at Duke Energy Ohio.