v2.4.0.6

Fair Value Of Financial Assets And Liabilities (Quantitative Level 3 Fair Value Disclosure) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012
Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | $ (85) | $ (53)
Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per MMBtu | 10.30 | 9.99
Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per MMBtu | 2.84 | 2.33
FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (10) | (23)
FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 54.56 | 48.69
FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 25.35 | 25.83
Financial Transmission Rights [Member] | RTO Market Pricing [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | 4 | 11
Financial Transmission Rights [Member] | RTO Market Pricing [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price FTR | 12.72 | 39.22
Financial Transmission Rights [Member] | RTO Market Pricing [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price FTR | (0.42) | 23.63
Commodity Power Contracts [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | 17 | (8)
Commodity Power Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 81.60 | 77.96
Commodity Power Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 28.40 | 24.82
Commodity Capacity Contracts [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (3) | (3)
Commodity Capacity Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per Mwd | 122.64 | 105.36
Commodity Capacity Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per Mwd | 95.16 | 95.16
Commodity Capacity Option Contracts [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | 2 |
Commodity Capacity Option Contracts [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure |  | 3
Commodity Capacity Option Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per Mwd | 81.60 | 77.96
Commodity Capacity Option Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per Mwd | 31.15 | 4.68
Derivative Financial Instruments Liabilities Reserves [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (7) | (12)
Duke Energy Carolinas [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (5) | (12)
Duke Energy Carolinas [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 54.56 | 48.69
Duke Energy Carolinas [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 28.18 | 25.83
Progress Energy [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (26) | (27)
Progress Energy [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per MMBtu | 4.54 | 4.45
Progress Energy [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per MMBtu | 4.13 | 4.07
Progress Energy [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (5) | (11)
Progress Energy [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 48.68 | 48.69
Progress Energy [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 25.35 | 25.83
Duke Energy Progress [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (26) | (27)
Duke Energy Progress [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per MMBtu | 4.54 | 4.45
Duke Energy Progress [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per MMBtu | 4.13 | 4.07
Duke Energy Progress [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (5) | (11)
Duke Energy Progress [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 48.68 | 48.69
Duke Energy Progress [Member] | FERC Mitigation Power Sale Agreements [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 25.35 | 25.83
Duke Energy Ohio [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (23) | 5
Duke Energy Ohio [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per MMBtu | 4.69 | 4.51
Duke Energy Ohio [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair Value Inputs Price Per MMBtu | 3.98 | 3.30
Duke Energy Ohio [Member] | Financial Transmission Rights [Member] | RTO Market Pricing [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure |  | 1
Duke Energy Ohio [Member] | Financial Transmission Rights [Member] | RTO Market Pricing [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price FTR |  | 39.22
Duke Energy Ohio [Member] | Financial Transmission Rights [Member] | RTO Market Pricing [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price FTR |  | 27.17
Duke Energy Ohio [Member] | Commodity Power Contracts [Member] | Discounted Cash Flow [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | 25 | (1)
Duke Energy Ohio [Member] | Commodity Power Contracts [Member] | Discounted Cash Flow [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 61.35 | 57.50
Duke Energy Ohio [Member] | Commodity Power Contracts [Member] | Discounted Cash Flow [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price per MWh | 28.40 | 25.90
Duke Energy Ohio [Member] | Derivative Financial Instruments Liabilities Reserves [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | (7) | (11)
Duke Energy Indiana [Member] | Financial Transmission Rights [Member] | RTO Market Pricing [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative Financial Instruments Liabilities Fair Value Disclosure | $ 4 | $ 10
Duke Energy Indiana [Member] | Financial Transmission Rights [Member] | RTO Market Pricing [Member] | Maximum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price FTR | 12.72 | 35.43
Duke Energy Indiana [Member] | Financial Transmission Rights [Member] | RTO Market Pricing [Member] | Minimum [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fair value inputs, price FTR | (0.42) | 23.63

X
- Definition Price per FTR, used as an input to measure fair value for financial transmission rights agreements. + References No definition available. + Details
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- Definition Price per MMBtu, used as an input to measure fair value for power sale agreements. + References No definition available. + Details
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- Definition Price per MW day, used as an input to measure fair value for power sale agreements. + References No definition available. + Details
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- Definition Price per MWh, used as an input to measure fair value for power sale agreements. + References No definition available. + Details
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- Definition Derivative instrument obligations meeting the definition of a liability which the Company is a party to as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 15 -Paragraph 83 -URI http://asc.fasb.org/extlink&oid=6913464&loc=d3e34841-113949 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 10 -Subparagraph i -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 6 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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