Employee Benefit Plans (Amounts Recognized in Consolidated Balance Sheets) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	$ 1,322		$ 2,520
Regulatory assets	10,086		11,741
Regulatory liabilities	6,265		5,740
Excluded Accumulated Other Comprehensive Income [Abstract]
Accumulated other comprehensive (loss) income, net of tax	(399)		(306)
Duke Energy Carolinas [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	161		221
Regulatory assets	1,822		1,948
Regulatory liabilities	2,641		2,180
Excluded Accumulated Other Comprehensive Income [Abstract]
Accumulated other comprehensive (loss) income, net of tax	(15)		(16)
Progress Energy [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	765		1,608
Regulatory assets	4,508		5,548
Regulatory liabilities	2,499		2,497
Excluded Accumulated Other Comprehensive Income [Abstract]
Accumulated other comprehensive (loss) income, net of tax	(59)		(67)
Duke Energy Progress [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	321		715
Regulatory assets	1,511		1,922
Regulatory liabilities	1,736		1,548
Duke Energy Florida [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	286		610
Regulatory assets	2,950		3,500
Regulatory liabilities	762		805
Excluded Accumulated Other Comprehensive Income [Abstract]
Accumulated other comprehensive (loss) income, net of tax	(1)		0
Duke Energy Ohio [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	58		157
Regulatory assets	528		625
Regulatory liabilities	289		293
Excluded Accumulated Other Comprehensive Income [Abstract]
Accumulated other comprehensive (loss) income, net of tax	0		(1)
Duke Energy Indiana [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	163		186
Regulatory assets	835		936
Regulatory liabilities	798		752
Excluded Accumulated Other Comprehensive Income [Abstract]
Accumulated other comprehensive (loss) income, net of tax	3		5
Qualified Pension Plans [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	632	[1]	163	[1]
Noncurrent pension liability			439
Net amount recognized	632		(276)
Regulatory assets	1,599		2,387
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	(41)		(59)
Prior year service cost (credit) arising during the year	(5)		(4)
Net actuarial loss (gain)	121		166
Net amount recognized in accumulated other comprehensive (income) loss	75	[2]	103	[2]
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	149
Unrecognized prior service (credit) cost	(15)
Qualified Pension Plans [Member] | Brazilian Retirement Plan [Member]
Excluded Accumulated Other Comprehensive Income [Abstract]
Accumulated other comprehensive (loss) income, net of tax	16		9
Qualified Pension Plans [Member] | Duke Energy Carolinas [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	287	[1]	123	[1]
Net amount recognized	287		123
Regulatory assets	377		582
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	35
Unrecognized prior service (credit) cost	(8)
Qualified Pension Plans [Member] | Progress Energy [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	230	[1]
Noncurrent pension liability	25		221
Net amount recognized	205		(221)
Regulatory assets	826		1,079
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	(9)		(9)
Net actuarial loss (gain)	21		26
Net amount recognized in accumulated other comprehensive (income) loss	12		17
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	71
Unrecognized prior service (credit) cost	(4)
Qualified Pension Plans [Member] | Duke Energy Progress [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	158	[1]	25	[1]
Net amount recognized	158		25
Regulatory assets	363		472
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	33
Unrecognized prior service (credit) cost	(2)
Qualified Pension Plans [Member] | Duke Energy Florida [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	66	[1]
Noncurrent pension liability			159
Net amount recognized	66		(159)
Regulatory assets	395		541
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	32
Unrecognized prior service (credit) cost	(1)
Qualified Pension Plans [Member] | Duke Energy Ohio [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	2	[1]
Noncurrent pension liability	(4)		81
Net amount recognized	6		(81)
Regulatory assets	48		144
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	4
Qualified Pension Plans [Member] | Duke Energy Indiana [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Prefunded pension	75	[1]
Noncurrent pension liability	53		57
Net amount recognized	22		(57)
Regulatory assets	147		246
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	7
Non-Qualified Pension Plans [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	30	[3]	30	[3]
Noncurrent pension liability	274		305
Total accrued pension liability	304		335
Regulatory assets	45		59
Regulatory liabilities	7		2
Accumulated Other Comprehensive Income (Loss) [Abstract]
Prior year service cost (credit) arising during the year	(1)
Net actuarial loss (gain)	1		(1)
Net amount recognized in accumulated other comprehensive (income) loss	0		(1)
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	5
Unrecognized prior service (credit) cost	(1)
Non-Qualified Pension Plans [Member] | Duke Energy Carolinas [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	2	[3]	3	[3]
Noncurrent pension liability	13		13
Total accrued pension liability	15		16
Regulatory assets	4		3
Non-Qualified Pension Plans [Member] | Progress Energy [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	11	[3]	11	[3]
Noncurrent pension liability	129		165
Total accrued pension liability	140		176
Regulatory assets	18		34
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax asset	(3)		(4)
Net actuarial loss (gain)	7		12
Net amount recognized in accumulated other comprehensive (income) loss	4		8
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	2
Unrecognized prior service (credit) cost	(1)
Non-Qualified Pension Plans [Member] | Duke Energy Progress [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	2	[3]	2	[3]
Noncurrent pension liability	32		36
Total accrued pension liability	34		38
Regulatory assets	3		7
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	1
Unrecognized prior service (credit) cost	(1)
Non-Qualified Pension Plans [Member] | Duke Energy Florida [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	3	[3]	3	[3]
Noncurrent pension liability	36		42
Total accrued pension liability	39		45
Regulatory assets	6		9
Non-Qualified Pension Plans [Member] | Duke Energy Ohio [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	3		4
Total accrued pension liability	3		4
Non-Qualified Pension Plans [Member] | Duke Energy Indiana [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	5		5
Total accrued pension liability	5		5
Regulatory assets			2
Other Post-Retirement Benefit Plans [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	39	[3]	50	[3]
Noncurrent pension liability	853		1,546
Total accrued pension liability	892		1,596
Regulatory assets	(162)		521
Regulatory liabilities	131		101
Accumulated Other Comprehensive Income (Loss) [Abstract]
Deferred income tax liability	4		2
Prior year service cost (credit) arising during the year	(5)		(3)
Net actuarial loss (gain)	(6)		(2)
Net amount recognized in accumulated other comprehensive (income) loss	(7)		(3)
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	38
Unrecognized prior service (credit) cost	(125)
Other Post-Retirement Benefit Plans [Member] | Duke Energy Carolinas [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	122		182
Total accrued pension liability	122		182
Regulatory assets	(34)		17
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	3
Unrecognized prior service (credit) cost	(10)
Other Post-Retirement Benefit Plans [Member] | Progress Energy [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	36	[3]	47	[3]
Noncurrent pension liability	497		1,081
Total accrued pension liability	533		1,128
Regulatory assets	(129)		505
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	46
Unrecognized prior service (credit) cost	(112)
Other Post-Retirement Benefit Plans [Member] | Duke Energy Progress [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	17	[3]	23	[3]
Noncurrent pension liability	216		589
Total accrued pension liability	233		612
Regulatory assets	(97)		291
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	30
Unrecognized prior service (credit) cost	(73)
Other Post-Retirement Benefit Plans [Member] | Duke Energy Florida [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	16	[3]	20	[3]
Noncurrent pension liability	237		393
Total accrued pension liability	253		413
Regulatory assets	4		170
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	10
Unrecognized prior service (credit) cost	(21)
Other Post-Retirement Benefit Plans [Member] | Duke Energy Ohio [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Current pension liability	2	[3]	2	[3]
Noncurrent pension liability	32		39
Total accrued pension liability	34		41
Regulatory liabilities	21		18
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	(2)
Other Post-Retirement Benefit Plans [Member] | Duke Energy Indiana [Member]
Amounts Recognized in Consolidated Balance Sheets [Abstract]
Noncurrent pension liability	100		119
Total accrued pension liability	100		119
Regulatory assets	71		77
Regulatory liabilities	77		68
Amounts to be recognized in net periodic pension expense in the next year [Abstract]
Unrecognized net actuarial loss	$ (6)

[1] Included in Other within Investments and Other Assets on the Consolidated Balance Sheets.

[2] Excludes accumulated other comprehensive income of $16 million and $9 million as of 2013 and 2012, respectively, net of tax, associated with a Brazilian retirement plan.

[3] Included in Other within Current Liabilities on the Consolidated Balance Sheets.