v2.4.0.6

Fair Value Of Financial Assets And Liabilities (Additional Fair Value Disclosure) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2013 | Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Long-term Debt, Fair Value | $ 44,068 |  | $ 44,001 |
Debt of variable interest entities | 1,255 |  | 852 |
Long-term Debt | 39,662 | [1] | 39,461 | [1]
Duke Energy Carolinas [Member] |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Long-term Debt, Fair Value | 10,036 |  | 10,096 |
Debt of variable interest entities | 300 |  | 300 |
Long-term Debt | 8,740 | [2] | 8,741 | [2]
Progress Energy [Member] |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Long-term Debt, Fair Value | 16,276 |  | 16,563 |
Long-term Debt | 14,224 |  | 14,428 |
Duke Energy Progress [Member] |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Long-term Debt, Fair Value | 5,757 |  | 5,277 |
Long-term Debt | 5,336 |  | 4,840 |
Duke Energy Florida [Member] |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Long-term Debt, Fair Value | 5,730 |  | 6,222 |
Long-term Debt | 4,894 |  | 5,320 |
Duke Energy Ohio [Member] |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Long-term Debt, Fair Value | 2,142 |  | 2,117 |
Long-term Debt | 1,994 |  | 1,997 |
Duke Energy Indiana [Member] |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |  |
Long-term Debt, Fair Value | 4,228 |  | 4,268 |
Long-term Debt | $ 3,702 |  | $ 3,702 |
[1] | Includes book value of Non-recourse long-term debt of variable interest entities of $1,255 million and $852 million March 31, 2013 and December 31, 2012, respectively.
[2] | Includes book value of Non-recourse long-term debt of variable interest entities of $300 million at both March 31, 2013 and December 31, 2012, respectively.

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- Definition debt of variable interest entities + References No definition available. + Details
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- Definition Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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