Risk Management, Derivative Instruments And Hedging Activities (Cash Flow Hedges - Location And Amount Of Pre-Tax Recognized In Comprehensive Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gains (losses) recorded in AOCI	$ 14		$ 18
Total Pre-tax Gains and (Losses) Reclassified from AOCI into Earnings	(1)		(1)
Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gains (losses) recorded in AOCI	13		18
Total Pre-tax Gains and (Losses) Reclassified from AOCI into Earnings	(1)	[1]	(1)	[1]
Commodity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gains (losses) recorded in AOCI	1
Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gains (losses) recorded in AOCI	1	[2]	4	[2]
Total Pre-tax Gains and (Losses) Reclassified from AOCI into Earnings			(4)	[2]
Progress Energy [Member] | Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gains (losses) recorded in AOCI			4	[2]
Total Pre-tax Gains and (Losses) Reclassified from AOCI into Earnings			(4)	[1],[2]
Progress Energy [Member] | Commodity Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gains (losses) recorded in AOCI	1	[2]
Duke Energy Progress [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gains (losses) recorded in AOCI	0	[3]	5	[3]
Total Pre-tax Gains and (Losses) Reclassified from AOCI into Earnings	0	[3]	(3)	[3]
Duke Energy Progress [Member] | Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of pre-tax gains (losses) recorded in AOCI	0	[1],[3]	5	[1],[3]
Total Pre-tax Gains and (Losses) Reclassified from AOCI into Earnings	$ 0	[1],[3]	$ (3)	[1],[3]

[1] Amounts in AOCI related to terminated hedges are reclassified to earnings as the interest expense is recorded. The effective portion of the hedges will be amortized to interest expense over the term of the related debt.

[2] Represents the gains and losses on cash flow hedges previously recorded in AOCI during the term of the hedging relationships and reclassified into earnings during the current period.

[3] Represents the gains and losses on cash flow hedges previously recorded in AOCI during the term of the hedging relationships and reclassified into earnings during the current period