v2.4.0.6

Debt And Credit Facilities (Summary Of Debt Issuances) (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended
--- | ---
Mar. 31, 2013 | Mar. 31, 2012
Debt Instrument [Line Items] |  |  |
Total Issuances | $ 1,653 |  |
Payments for the redemption of long-term debt | 747 |  | 821
Unsecured Debt [Member] | January 2013 [Member] | January 2073 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Unsecured debt issuances | 500 | [1] |
Interest Rate | 5.125% |  |
Debt instrument, call date, earliest | Jan. 01, 2018 |  |
Secured Debt [Member] | June 2013 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest Rate | 1.009% |  |
Secured Debt [Member] | April 2013 [Member] | April 2026 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Secured debt issuances | 230 | [2] |
Interest Rate | 5.456% |  |
Percentage of debt hedged by interest rate derivatives | 75.00% |  |
Incremental debt proceeds | 40 |  |
Secured Debt [Member] | February 2013 [Member] | June 2037 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Secured debt issuances | 220 | [3] |
Interest Rate | 4.74% |  |
Secured Debt [Member] | February 2013 [Member] | December 2030 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Secured debt issuances | 203 | [3],[4] |
Interest Rate | 2.043% |  |
Percentage of debt hedged by interest rate derivatives | 95.00% |  |
Secured Debt [Member] | Bridge Loan [Member] | June 2013 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Payments for the redemption of long-term debt | 190 |  |
First Mortgage Bonds [Member] | March 2013 [Member] | March 2043 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
First mortgage bonds issuances | 500 | [5] |
Interest Rate | 4.10% |  |
Duke Energy Carolinas [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Payments for the redemption of long-term debt | 0 |  | 751
Progress Energy [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Payments for the redemption of long-term debt | 736 |  | 1
Progress Energy [Member] | Corporate Debt Securities [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest Rate | 7.10% |  |
Payments for the redemption of long-term debt | 300 |  |
Duke Energy Progress [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Total Issuances | 500 |  |
Payments for the redemption of long-term debt | 1 |  | 0
Duke Energy Progress [Member] | First Mortgage Bonds [Member] | March 2013 [Member] | March 2043 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
First mortgage bonds issuances | 500 | [5] |
Interest Rate | 4.10% |  |
Duke Energy Florida [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Payments for the redemption of long-term debt | 426 |  | 1
Duke Energy Ohio [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Payments for the redemption of long-term debt | 2 |  | 2
Duke Energy Ohio [Member] | First Mortgage Bonds [Member] | June 2013 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest Rate | 2.10% |  |
Duke Energy Indiana [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Payments for the redemption of long-term debt | 1 |  | 1
Parent Company [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Total Issuances | 500 |  |
Parent Company [Member] | Unsecured Debt [Member] | June 2013 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Interest Rate | 5.65% |  |
Parent Company [Member] | Unsecured Debt [Member] | January 2013 [Member] | January 2073 [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Unsecured debt issuances | $ 500 | [1] |
Interest Rate | 5.125% |  |
Debt instrument, call date, earliest | Jan. 01, 2018 |  |
[1] | Callable after January 2018 at par. Proceeds from the issuance were used to redeem the $300 million 7.10% Cumulative Quarterly Income Preferred Securities (QUIPS). The securities were redeemed at par plus accrued and unpaid distributions, payable upon presentation on the redemption date. The remaining net proceeds were used to repay a portion of our commercial paper and for general corporate purposes. See Note 11 for additional information about the QUIPS.
[2] | Represents primarily the conversion of a $190 million bridge loan issued in conjunction with the acquisition of Ibener in December 2012. Duke Energy received incremental proceeds of $40 million upon conversion of the bridge loan. The debt is floating rate and is denominated in U.S. dollars. Duke Energy has entered into a pay fixed-receive floating interest rate swap for 75 percent of the loan.
[3] | Represents the conversion of construction loans related to a renewable energy project issued in December 2012 to term loans. No cash proceeds were received in conjunction with the conversion. The term loans have varying maturity dates. The maturity date presented represents the latest date for all components of the respective loans.
[4] | The debt is floating rate. Duke Energy has entered into a pay fixed-receive floating interest rate swap for 95 percent of the loans.
[5] | Proceeds from the issuance were used to repay notes payable to affiliated companies as well as for general corporate purposes.

X
- Definition Sum of the debt issuances during the reported period at face value. + References No definition available. + Details
Name: | duk_DebtIssuancesTotal
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition First Mortgage Bonds issued during the reported period. + References No definition available. + Details
Name: | duk_FirstMortgageBondsIssuances
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer) issued during the reported period. Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower. + References No definition available. + Details
Name: | duk_SecuredDebtIssuances
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Including the current and noncurrent portions issued during the reported period, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer). + References No definition available. + Details
Name: | duk_UnsecuredDebtIssuances
Namespace Prefix: | duk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Earliest date before maturity when the issuer can call the outstanding debt instrument for repayment or conversion to equity, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 -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
Name: | us-gaap_DebtInstrumentCallDateEarliest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Interest rate stated in the contractual debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 2: 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(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of an entity's outstanding debt that is designated as a hedged item in cash flow, fair value, or net investment hedge. + References No definition available. + Details
Name: | us-gaap_PercentageOfDebtHedgedByInterestRateDerivatives
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 -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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfSecuredDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 -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 -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3291-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -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
Name: | us-gaap_RepaymentsOfLongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration