v2.4.0.6

Risk Management, Derivative Instruments And Hedging Activities (Derivative Instruments That Contain Credit-Risk Related Contingent Features and Cash Collateral) (Details) (USD $) In Millions, unless otherwise specified | Mar. 31, 2013 | Mar. 31, 2012
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Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features |  |
Aggregate fair value amounts of derivative instruments in a net liability position | $ 512 | $ 466
Collateral aready posted | 215 | 163
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered at the end of the reporting period | 202 | 230
Information Regarding Cash Collateral Under Master Netting Arrangements |  |
Amounts offset against derivative positions on the net condensed Consolidated Balance Sheets, Receivables | 107 | 73
Derivative, collateral, obligation to return cash - not offset against net derivative | 108 | 93
Progress Energy [Member] |  |
Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features |  |
Aggregate fair value amounts of derivative instruments in a net liability position | 230 | 286
Collateral aready posted | 35 | 59
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered at the end of the reporting period | 195 | 227
Information Regarding Cash Collateral Under Master Netting Arrangements |  |
Amounts offset against derivative positions on the net condensed Consolidated Balance Sheets, Receivables | 35 | 58
Derivative, collateral, obligation to return cash - not offset against net derivative |  | 1
Duke Energy Progress [Member] |  |
Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features |  |
Aggregate fair value amounts of derivative instruments in a net liability position | 79 | 108
Collateral aready posted | 3 | 9
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered at the end of the reporting period | 76 | 99
Information Regarding Cash Collateral Under Master Netting Arrangements |  |
Amounts offset against derivative positions on the net condensed Consolidated Balance Sheets, Receivables | 3 | 9
Duke Energy Florida [Member] |  |
Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features |  |
Aggregate fair value amounts of derivative instruments in a net liability position | 151 | 178
Collateral aready posted | 32 | 50
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered at the end of the reporting period | 119 | 128
Information Regarding Cash Collateral Under Master Netting Arrangements |  |
Amounts offset against derivative positions on the net condensed Consolidated Balance Sheets, Receivables | 32 | 49
Derivative, collateral, obligation to return cash - not offset against net derivative |  | 1
Duke Energy Ohio [Member] |  |
Schedule Of Information Regarding Derivative Instruments That Contain Credit-Risk Related Contingent Features |  |
Aggregate fair value amounts of derivative instruments in a net liability position | 279 | 176
Collateral aready posted | 180 | 104
Additional cash collateral or letters of credit in the event credit-risk-related contingent features were triggered at the end of the reporting period | 7 | 2
Information Regarding Cash Collateral Under Master Netting Arrangements |  |
Amounts offset against derivative positions on the net condensed Consolidated Balance Sheets, Receivables | 72 | 15
Derivative, collateral, obligation to return cash - not offset against net derivative | $ 108 | $ 92

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- Definition The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44D -Subparagraph c -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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- Definition The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44D -Subparagraph c -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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624258-113959 + Details
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- Definition The amount of the obligation to return cash collateral under master netting arrangements that have not been offset against net derivative instrument positions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 + Details
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- Definition The amount as of the balance sheet date of the fair value of derivative assets that in accordance with the entity's accounting policy was offset against an obligation to return cash collateral under a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FIN39-1 -Paragraph 10B -Subparagraph b -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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- Definition The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44D -Subparagraph b -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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