v2.4.0.6
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
 3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities $ 113 $ 26
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (139) 36
Interest Rate Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 13 22
Interest Rate Contracts [Member] | Interest Expense [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense (4)  
Commodity Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 105 (1)
Commodity Contracts [Member] | Regulatory Liability [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities (5) 5
Commodity Contracts [Member] | Revenue Regulated Electric [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts 6  
Commodity Contracts [Member] | Revenue Non Regulated Electric Natural Gas And Other [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (82) 36
Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Regulated [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (52)  
Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Non Regulated [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (7)  
Progress Energy [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 110 (206)
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (50) (97)
Progress Energy [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 5  
Progress Energy [Member] | Interest Rate Contracts [Member] | Interest Expense [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense (4)  
Progress Energy [Member] | Commodity Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 105 (206)
Progress Energy [Member] | Commodity Contracts [Member] | Revenue Regulated Electric [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts 6  
Progress Energy [Member] | Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Regulated [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (52) (105)
Progress Energy [Member] | CVOs [Member] | Other Income And Expense [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts   8
Duke Energy Progress [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 39 (59)
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (14) (26)
Duke Energy Progress [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 3 [1]  
Duke Energy Progress [Member] | Interest Rate Contracts [Member] | Interest Expense [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense (3)  
Duke Energy Progress [Member] | Commodity Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 36 [2] (59) [2]
Duke Energy Progress [Member] | Commodity Contracts [Member] | Revenue Regulated Electric [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts 6  
Duke Energy Progress [Member] | Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Regulated [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (17) [3] (26) [3]
Duke Energy Florida [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 70 (147)
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (36) (79)
Duke Energy Florida [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 1  
Duke Energy Florida [Member] | Interest Rate Contracts [Member] | Interest Expense [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized in Earnings - Interest Expense (1)  
Duke Energy Florida [Member] | Commodity Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 69 [4] (147) [4]
Duke Energy Florida [Member] | Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Regulated [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (35) [3] (79) [3]
Duke Energy Ohio [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 1 (1)
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (98) 71
Duke Energy Ohio [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 1 1
Duke Energy Ohio [Member] | Commodity Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities   (2)
Duke Energy Ohio [Member] | Commodity Contracts [Member] | Revenue Non Regulated Electric Natural Gas And Other [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (91) 71
Duke Energy Ohio [Member] | Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Non Regulated [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Pre-tax gains losses on derivative instruments Recognized in Earnings - Non Interest rate contracts (7)  
Duke Energy Indiana [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 12 25
Duke Energy Indiana [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities 8 21
Duke Energy Indiana [Member] | Commodity Contracts [Member] | Regulatory Liability [Member]
    
Derivative Instruments, Gain (Loss) [Line Items]    
Total Pre-tax Gains (Losses) Recognized as Regulatory Assets or Liabilities $ 4 $ 4
[1] Amounts in regulatory assets and liabilities related to terminated hedges are reclassified to earnings as the interest expense is recorded. The hedges will be amortized to interest expense over the term of the related debt.
[2] Amounts are recorded in regulatory assets and liabilities in the Condensed Consolidated Balance Sheets until gains or losses are passed through the fuel cost-recovery clause.
[3] After the settlement of the derivatives and the consumption of fuel, gains or losses are passed through the fuel cost-recovery clause.
[4] Amounts are recorded in regulatory assets and liabilities in the Condensed Balance Sheets until gains or losses are passed through the fuel cost-recovery clause.