Risk Management, Derivative Instruments And Hedging Activities (Undesignated Contracts - Location And Amount Of Pre-Tax Gains And (Losses) Recognized In Income Or As Regulatory Assets Or Liabilities) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	$ 44	$ (209)	$ 78
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(187)	(60)	(28)
Duke Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities		(154)	59
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(12)		1
Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	(165)	(502)	(398)
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(466)	(355)	(323)
Progress Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	(49)	(140)	(77)
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(132)	(59)	(45)
Progress Energy Florida [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	(116)	(362)	(321)
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(341)	(237)	(278)
Duke Energy Ohio [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	1	(3)	4
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	77	(28)	5
Interest Rate Contract [Member] | Regulatory Asset [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	10	(165)	(1)
Interest Rate Contract [Member] | Regulatory Asset [Member] | Duke Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities		(94)
Interest Rate Contract [Member] | Regulatory Asset [Member] | Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	6
Interest Rate Contract [Member] | Regulatory Asset [Member] | Progress Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	6
Interest Rate Contract [Member] | Regulatory Asset [Member] | Duke Energy Ohio [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities		(4)	(1)
Interest Rate Contract [Member] | Regulatory Asset [Member] | Duke Energy Indiana [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	4	(67)
Interest Rate Contract [Member] | Regulatory Liability [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities		(60)	60
Interest Rate Contract [Member] | Regulatory Liability [Member] | Duke Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities		(60)	60
Commodity Contract [Member] | Regulatory Asset [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	(2)	(1)	5
Commodity Contract [Member] | Regulatory Asset [Member] | Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	(171)	(502)	(398)
Commodity Contract [Member] | Regulatory Asset [Member] | Progress Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	(55)	(140)	(77)
Commodity Contract [Member] | Regulatory Asset [Member] | Progress Energy Florida [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	(116)	(362)	(321)
Commodity Contract [Member] | Regulatory Asset [Member] | Duke Energy Ohio [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	2	1	5
Commodity Contract [Member] | Regulatory Asset [Member] | Duke Energy Indiana [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	2	(2)
Commodity Contract [Member] | Regulatory Liability [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	36	17	14
Commodity Contract [Member] | Regulatory Liability [Member] | Duke Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities			(1)
Commodity Contract [Member] | Regulatory Liability [Member] | Duke Energy Ohio [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	(1)
Commodity Contract [Member] | Regulatory Liability [Member] | Duke Energy Indiana [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities	35	17	14
Revenue Regulated Electric [Member] | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(23)		1
Revenue Regulated Electric [Member] | Commodity Contract [Member] | Duke Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(12)		1
Revenue Regulated Electric [Member] | Commodity Contract [Member] | Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(11)	1	1
Revenue Regulated Electric [Member] | Commodity Contract [Member] | Progress Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(11)	1	1
Revenue Non Regulated Electric Natural Gas And Other [Member] | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	38	(59)	(38)
Revenue Non Regulated Electric Natural Gas And Other [Member] | Commodity Contract [Member] | Duke Energy Ohio [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	76	(26)	(3)
Fuel Used In Electric Generation And Purchased Power Regulated [Member] | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(194)
Fuel Used In Electric Generation And Purchased Power Regulated [Member] | Commodity Contract [Member] | Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(454)	(297)	(324)
Fuel Used In Electric Generation And Purchased Power Regulated [Member] | Commodity Contract [Member] | Progress Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(115)	(60)	(46)
Fuel Used In Electric Generation And Purchased Power Regulated [Member] | Commodity Contract [Member] | Progress Energy Florida [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(339)	(237)	(278)
Fuel Used In Electric Generation And Purchased Power Non Regulated [Member] | Commodity Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	2	(1)	9
Fuel Used In Electric Generation And Purchased Power Non Regulated [Member] | Commodity Contract [Member] | Duke Energy Ohio [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	2	(1)	9
Other Income And Expense [Member] | CVOs [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	(2)
Other Income And Expense [Member] | CVOs [Member] | Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts	7	(59)
Interest Expense [Member] | Interest Rate Contract [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense	(8)
Interest Expense [Member] | Interest Rate Contract [Member] | Progress Energy [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense	(8)
Interest Expense [Member] | Interest Rate Contract [Member] | Progress Energy Carolinas [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense	(6)
Interest Expense [Member] | Interest Rate Contract [Member] | Progress Energy Florida [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense	(2)
Interest Expense [Member] | Interest Rate Contract [Member] | Duke Energy Ohio [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense	$ (1)	$ (1)	$ (1)