v2.4.0.8

Derivatives and Hedging (Undesignated Contracts - Location and Amount of Pretax Gains and (Losses) Recognized in Income or As Regulatory Assets or Liabilities) (Details) (Not Designated as Hedging Instrument [Member], USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings | $ (278) | $ (78) | $ (807) | $ (195)
Pretax gains (losses) recognized as regulatory assets or liabilities | (15) | (11) | 27 | 27
Commodity Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities | 3 | (29) | 2 | (34)
Commodity Contracts [Member] | Regulatory Liability [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities | 1 | 6 |  | 10
Commodity Contracts [Member] | Revenue Regulated Electric [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities |  | 3 |  | 10
Commodity Contracts [Member] | Revenue Non Regulated Electric Natural Gas And Other [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities |  | (7) |  | (7)
Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Regulated [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | 32 | (68) | 18 | (157)
Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Non Regulated [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities |  | (2) |  |
Commodity Contracts [Member] | Income (loss) from Discontinued Operations [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | (319) |  | (825) | (28)
Interest Rate Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities | (7) | 12 | 9 | 51
Interest Rate Contracts [Member] | Regulatory Liability [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities | (12) |  | 16 |
Interest Rate Contracts [Member] | Interest Expense [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | 9 | (4) |  | (13)
Progress Energy [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings | 33 | (69) | 18 | (160)
Pretax gains (losses) recognized as regulatory assets or liabilities | 3 | (27) | 19 | (21)
Progress Energy [Member] | Commodity Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities | 3 | (31) | 19 | (34)
Progress Energy [Member] | Commodity Contracts [Member] | Revenue Regulated Electric [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | 1 | 3 |  | 10
Progress Energy [Member] | Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Regulated [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | 32 | (68) | 18 | (157)
Progress Energy [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities |  | 4 |  | 13
Progress Energy [Member] | Interest Rate Contracts [Member] | Interest Expense [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - interest |  | (4) |  | (13)
Duke Energy Progress [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings | 14 | (24) | 4 | (52)
Pretax gains (losses) recognized as regulatory assets or liabilities | (19) | (8) | 21 | (8)
Duke Energy Progress [Member] | Commodity Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities | (19) | (11) | 21 | (18)
Duke Energy Progress [Member] | Commodity Contracts [Member] | Revenue Regulated Electric [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | 1 | 3 |  | 10
Duke Energy Progress [Member] | Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Regulated [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | 13 | (24) | 4 | (53)
Duke Energy Progress [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities |  | 3 |  | 10
Duke Energy Progress [Member] | Interest Rate Contracts [Member] | Interest Expense [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - interest |  | (3) |  | (9)
Duke Energy Florida [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings | 20 | (46) | 14 | (108)
Pretax gains (losses) recognized as regulatory assets or liabilities | 22 | (18) | (2) | (13)
Duke Energy Florida [Member] | Commodity Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities | 22 | (19) | (2) | (16)
Duke Energy Florida [Member] | Commodity Contracts [Member] | Fuel Used In Electric Generation And Purchased Power Regulated [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | 20 | (45) | 14 | (105)
Duke Energy Florida [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities |  | 1 |  | 3
Duke Energy Florida [Member] | Interest Rate Contracts [Member] | Interest Expense [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - interest |  | (1) |  | (3)
Duke Energy Ohio [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings | (303) | 3 | (888) | (29)
Pretax gains (losses) recognized as regulatory assets or liabilities |  |  | 5 | 3
Duke Energy Ohio [Member] | Commodity Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities |  |  | (1) |
Duke Energy Ohio [Member] | Commodity Contracts [Member] | Income (loss) from Discontinued Operations [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - commodities | (303) | 3 | (887) | (28)
Duke Energy Ohio [Member] | Interest Rate Contracts [Member] | Regulatory Asset [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities |  |  |  | 3
Duke Energy Ohio [Member] | Interest Rate Contracts [Member] | Regulatory Liability [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized as regulatory assets or liabilities |  |  | 6 |
Duke Energy Ohio [Member] | Interest Rate Contracts [Member] | Interest Expense [Member] |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Pretax gains (losses) recognized in earnings - interest |  |  | $ (1) | $ (1)

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- Definition Unrealized gain or (loss) amounts are recorded in regulatory liabilities and assets, respectively until derivatives are settled. + References No definition available. + Details
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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959 + Details
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- Definition Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959 + Details
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- Definition Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of price risk derivatives not designated as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959 + Details
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