Derivatives and Hedging (Cash Flow Hedges - Location and Amount of PreTax Recognized in Comprehensive Income) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	$ (1,546)	$ (1,242)	$ (859)
Designated As Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total pretax gains (losses) recorded in AOCI	80	(22)	(88)
Designated As Hedging Instrument [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	2	(2)	5
Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses) recorded in AOCI - interest rate contracts	79	(23)	(88)
Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	2	(2)	5
Designated As Hedging Instrument [Member] | Commodity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses) recorded in AOCI - commodity contracts	1	1
Duke Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	(359)	(384)	(360)
Duke Energy Carolinas [Member] | Designated As Hedging Instrument [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	3	3	5
Duke Energy Carolinas [Member] | Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	3	3	5
Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	(680)	(740)	(725)
Progress Energy [Member] | Designated As Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total pretax gains (losses) recorded in AOCI	1	(10)	(144)
Progress Energy [Member] | Designated As Hedging Instrument [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense		14	13
Pretax gains and (losses) recognized in earnings on derivatives		(159)
Progress Energy [Member] | Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses) recorded in AOCI - interest rate contracts		(11)	(141)
Progress Energy [Member] | Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense		14	13
Pretax gains and (losses) recognized in earnings on derivatives		(159)
Progress Energy [Member] | Designated As Hedging Instrument [Member] | Commodity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses) recorded in AOCI - commodity contracts	1	1	(3)
Duke Energy Progress [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	(201)	(207)	(184)
Duke Energy Progress [Member] | Designated As Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total pretax gains (losses) recorded in AOCI		(7)	(70)
Duke Energy Progress [Member] | Designated As Hedging Instrument [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense		5	7
Pretax gains and (losses) recognized in earnings on derivatives		(117)
Duke Energy Progress [Member] | Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses) recorded in AOCI - interest rate contracts		(7)	(70)
Duke Energy Progress [Member] | Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense		5	7
Pretax gains and (losses) recognized in earnings on derivatives		(117)
Duke Energy Florida [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	(180)	(255)	(239)
Duke Energy Florida [Member] | Designated As Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total pretax gains (losses) recorded in AOCI	1	(1)	(38)
Duke Energy Florida [Member] | Designated As Hedging Instrument [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense		2	1
Pretax gains and (losses) recognized in earnings on derivatives		(42)
Duke Energy Florida [Member] | Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses) recorded in AOCI - interest rate contracts		(2)	(35)
Duke Energy Florida [Member] | Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense		2	1
Pretax gains and (losses) recognized in earnings on derivatives		(42)
Duke Energy Florida [Member] | Designated As Hedging Instrument [Member] | Commodity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pretax gains (losses) recorded in AOCI - commodity contracts	1	1	(3)
Duke Energy Ohio [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	(78)	(89)	(104)
Duke Energy Indiana [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	(170)	(138)	(137)
Duke Energy Indiana [Member] | Designated As Hedging Instrument [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	(3)	(3)	(2)
Duke Energy Indiana [Member] | Designated As Hedging Instrument [Member] | Interest Rate Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest expense	$ (3)	$ (3)	$ (2)