2.4.0.8020101 - Disclosure - Organization and Basis of Presentation (Policy)truefalsefalse1false falsefalseFROM_Jan01_2013_TO_Jun30_2013http://www.sec.gov/CIK0001326160duration2013-01-01T00:00:002013-06-30T00:00:001true 3duk_PolicyTextBlockLineItemsduk_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Policy Text Block [Line Items]2false 4us-gaap_NatureOfOperationsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00NATURE OF OPERATIONS AND BASIS OF CONSOLIDATIONDuke Energy Corporation (collectively with its subsidiaries, Duke Energy), is an energy company headquartered in Charlotte, North Carolina, subject to regulation by the Federal Energy Regulatory Commission (FERC). Duke Energy operates in the United States (U.S.) and Latin America primarily through its direct and indirect subsidiaries. Duke Energy's subsidiaries include Duke Energy Carolinas, LLC (Duke Energy Carolinas); Progress Energy, Inc. (Progress Energy); Duke Energy Progress, Inc. (Duke Energy Progress); Duke Energy Florida, Inc. (Duke Energy Florida); Duke Energy Ohio, Inc. (Duke Energy Ohio) and Duke Energy Indiana, Inc. (Duke Energy Indiana). On July 2, 2012, Duke Energy merged with Progress Energy, with Duke Energy continuing as the surviving corporation, Progress Energy becoming a subsidiary of Duke Energy and Progress Energy's regulated utility subsidiaries, Duke Energy Progress (formerly Carolina Power & Light Company d/b/a Progress Energy Carolinas, Inc.) and Duke Energy Florida (formerly Florida Power Corporation d/b/a Progress Energy Florida , Inc.), becoming indirect subsidiaries of Duke Energy. Duke Energy's consolidated financial statements include Progress Energy, Duke Energy Progress and Duke Energy Florida activity beginning July 2, 2012. In accordance with Securities and Exchange Commission (SEC) guidance, Progress Energy, Duke Energy Progress and Duke Energy Florida did not reflect the impacts of acquisition accounting from the merger with Duke Energy, whereby the adjustments of assets and liabilities to fair value and the resultant goodwill would be shown on the financial statements of Progress Energy, Duke Energy Progress and Duke Energy Florida. These adjustments were recorded by Duke Energy. See Note 2 for additional information regarding the merger. When discussing Duke Energy's consolidated financial information, it necessarily includes the results of its six separate subsidiary registrants, Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida, Duke Energy Ohio and Duke Energy Indiana (collectively referred to as the Subsidiary Registrants), which, along with Duke Energy, are collectively referred to as the Duke Energy Registrants. The information in these combined notes relates to each of the Duke Energy Registrants as noted in the Index to Combined Notes. However, none of the registrants makes any representation as to information related solely to Duke Energy or the subsidiaries of Duke Energy other than itself. As discussed further in Note 3, Duke Energy operates three reportable business segments: U.S. Franchised Electric and Gas (USFE&G), Commercial Power and International Energy. The remainder of Duke Energy's operations is presented as Other.These Condensed Consolidated Financial Statements include, after eliminating intercompany transactions and balances, the accounts of the Duke Energy Registrants and all majority-owned subsidiaries where the respective Duke Energy Registrants have control and those variable interest entities (VIEs) where the respective Duke Energy Registrants are the primary beneficiary. These Condensed Consolidated Financial Statements also reflect the Duke Energy Registrants' proportionate share of certain generation and transmission facilities.Duke Energy Carolinas, a wholly owned subsidiary of Duke Energy, is a regulated public utility that generates, transmits, distributes and sells electricity in portions of North Carolina and South Carolina. Duke Energy Carolinas is subject to the regulatory provisions of the North Carolina Utilities Commission (NCUC), the Public Service Commission of South Carolina (PSCSC), the U.S. Nuclear Regulatory Commission (NRC) and the FERC. Substantially all of Duke Energy Carolinas' operations are regulated and qualify for regulatory accounting treatment. As discussed further in Note 3, Duke Energy Carolinas' operations include one reportable business segment, Franchised Electric. Progress Energy, a wholly owned subsidiary of Duke Energy, is a holding company headquartered in Raleigh, North Carolina, subject to regulation by the FERC. Progress Energy conducts operations through its wholly owned subsidiaries, Duke Energy Progress and Duke Energy Florida. As discussed further in Note 3, Progress Energy's operations include one reportable segment, Franchised Electric. Duke Energy Progress, an indirect wholly owned subsidiary of Duke Energy, is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of North Carolina and South Carolina. Duke Energy Progress is subject to the regulatory provisions of the NCUC, the PSCSC, the NRC and the FERC. Substantially all of Duke Energy Progress' operations are regulated and qualify for regulatory accounting treatment. As discussed further in Note 3, Duke Energy Progress' operations include one reportable segment, Franchised Electric.Duke Energy Florida, an indirect wholly owned subsidiary of Duke Energy, is a regulated public utility primarily engaged in the generation, transmission, distribution and sale of electricity in portions of Florida. Duke Energy Florida is subject to the regulatory jurisdiction of the Florida Public Service Commission (FPSC), the NRC and the FERC. Substantially all of Duke Energy Florida's operations are regulated and qualify for regulatory accounting treatment. As discussed further in Note 3, Duke Energy Florida's operations include one reportable segment, Franchised Electric.Duke Energy Ohio, an indirect wholly owned subsidiary of Duke Energy, is a combination electric and gas public utility that provides service in portions of Ohio and Kentucky through its wholly owned subsidiary, Duke Energy Kentucky, Inc. (Duke Energy Kentucky), as well as electric generation in portions of Ohio, Illinois and Pennsylvania. Duke Energy Ohio's principal lines of business include generation, transmission and distribution of electricity, the sale of and/or transportation of natural gas, and energy marketing. Duke Energy Ohio conducts competitive auctions for retail electricity supply in Ohio whereby the energy price is recovered from retail customers. Duke Energy Kentucky's principal lines of business include generation, transmission and distribution of electricity, as well as the sale of and/or transportation of natural gas. References herein to Duke Energy Ohio include Duke Energy Ohio and its subsidiaries, unless otherwise noted. Duke Energy Ohio is subject to the regulatory provisions of the Public Utilities Commission of Ohio (PUCO), the Kentucky Public Service Commission (KPSC) and the FERC. Duke Energy Ohio applies regulatory accounting treatment to substantially all of the operations in its Franchised Electric and Gas operating segment. See Note 3 for further information about Duke Energy Ohio's business segments. Duke Energy Indiana, an indirect wholly owned subsidiary of Duke Energy, is a regulated public utility that provides electricity service in portions of Indiana. Its primary line of business is generation, transmission and distribution of electricity. Duke Energy Indiana is subject to the regulatory provisions of the Indiana Utility Regulatory Commission (IURC) and the FERC. Substantially all of Duke Energy Indiana's operations are regulated and qualify for regulatory accounting treatment. As discussed further in Note 3, Duke Energy Indiana's operations include one reportable business segment, Franchised Electric.falsefalsefalsenonnum:textBlockItemTypenaThe entire disclosure for the nature of an entity's business, the major products or services it sells or provides and its principal markets, including the locations of those markets. If the entity operates in more than one business, the disclosure also indicates the relative importance of its operations in each business and the basis for the determination (for example, assets, revenues, or earnings).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6003-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-6 -Paragraph 10 -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. false0Organization3false 4us-gaap_UseOfEstimatesus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00BASIS OF PRESENTATIONThese Condensed Consolidated Financial Statements have been prepared in accordance with generally accepted accounting principles (GAAP) in the U.S. for interim financial information and with the instructions to Form 10-Q and Regulation S-X. Accordingly, these Condensed Consolidated Financial Statements do not include all of the information and notes required by GAAP in the U.S. for annual financial statements. Because the interim Condensed Consolidated Financial Statements and Notes do not include all of the information and notes required by GAAP in the U.S. for annual financial statements, the Condensed Consolidated Financial Statements and other information included in this quarterly report should be read in conjunction with the Consolidated Financial Statements and Notes in the Duke Energy Registrants' combined Form 10-K for the year ended December 31, 2012. These Condensed Consolidated Financial Statements, in the opinion of management, reflect all normal recurring adjustments that are, in the opinion of the respective companies' management, necessary to fairly present the financial position and results of operations of each Duke Energy Registrant. Amounts reported in Duke Energy's interim Condensed Consolidated Statements of Operations and each of the Subsidiary Registrants' interim Condensed Consolidated Statements of Income and Comprehensive Income are not necessarily indicative of amounts expected for the respective annual periods due to the effects of seasonal temperature variations on energy consumption, regulatory rulings, the timing of maintenance on electric generating units, changes in mark-to-market valuations, changing commodity prices and other factors. In preparing financial statements that conform to GAAP, management must make estimates and assumptions that affect the reported amounts of assets and liabilities, the reported amounts of revenues and expenses and the disclosure of contingent assets and liabilities at the date of the financial statements. Actual results could differ from those estimates.Prior year financial statements and footnote disclosures for Progress Energy, Duke Energy Progress and Duke Energy Florida have been reclassified to conform to Duke Energy's presentation.falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6143-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6132-108592 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6061-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Statement of Position (SOP) -Number 94-6 -Paragraph 11, 14 -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. false0Use Of Estimates4false 4us-gaap_RevenueRecognitionPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00UNBILLED REVENUERevenues on sales of electricity and gas are recognized when either the service is provided or the product is delivered. Unbilled retail revenues are estimated by applying average revenue per kilowatt-hour (kWh) or per thousand cubic feet (Mcf) for all customer classes to the number of estimated kWh or Mcf delivered but not billed. Unbilled wholesale energy revenues are calculated by applying the contractual rate per megawatt-hour (MWh) to the number of estimated MWh delivered but not yet billed. Unbilled wholesale demand revenues are calculated by applying the contractual rate per megawatt (MW) to the MW volume delivered but not yet billed. The amount of unbilled revenues can vary significantly from period to period as a result of numerous factors, including seasonality, weather, customer usage patterns and customer mix. The Duke Energy Registrants had unbilled revenues within Receivables and within Restricted receivables of variable interest entities on their respective Condensed Consolidated Balance Sheets as shown in the table below.Additionally, Duke Energy Ohio and Duke Energy Indiana sell, on a revolving basis, nearly all of their retail and wholesale accounts receivable to Cinergy Receivables Company, LLC (CRC). These transfers meet sales/derecognition criteria and, therefore, Duke Energy Ohio and Duke Energy Indiana account for the transfers of receivables to CRC as sales. Accordingly, the receivables sold are not reflected on the Condensed Consolidated Balance Sheets of Duke Energy Ohio and Duke Energy Indiana. See Note 11 for further information. Receivables for unbilled revenues related to retail and wholesale accounts receivable at Duke Energy Ohio and Duke Energy Indiana included in the sales of accounts receivable to CRC were as shown in the table below.falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18726-107790 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 13 -Section B -Paragraph Question 1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 13.B.Q1) -URI http://asc.fasb.org/extlink&oid=6600647&loc=d3e214044-122780 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 22 -Paragraph 8, 12, 13 -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18823-107790 false0Unbilled Revenue5false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_DukeEnergyOhioMemberhttp://www.sec.gov/CIK0001326160duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseDuke Energy Ohio [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiduk_DukeEnergyOhioMemberdei_LegalEntityAxisexplicitMembernanafalse0Duke Energy Ohio [Member]6true 3duk_PolicyTextBlockLineItemsduk_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Policy Text Block [Line Items]7false 4us-gaap_RevenueRecognitionPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00Additionally, Duke Energy Ohio and Duke Energy Indiana sell, on a revolving basis, nearly all of their retail and wholesale accounts receivable to Cinergy Receivables Company, LLC (CRC). These transfers meet sales/derecognition criteria and, therefore, Duke Energy Ohio and Duke Energy Indiana account for the transfers of receivables to CRC as sales. Accordingly, the receivables sold are not reflected on the Condensed Consolidated Balance Sheets of Duke Energy Ohio and Duke Energy Indiana. See Note 11 for further information. Receivables for unbilled revenues related to retail and wholesale accounts receivable at Duke Energy Ohio and Duke Energy Indiana included in the sales of accounts receivable to CRC were as shown in the table below.falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18726-107790 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 13 -Section B -Paragraph Question 1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 13.B.Q1) -URI http://asc.fasb.org/extlink&oid=6600647&loc=d3e214044-122780 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 22 -Paragraph 8, 12, 13 -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18823-107790 false0Unbilled Revenue8false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse3false truefalseFROM_Jan01_2013_TO_Jun30_2013_dei_LegalEntityAxis_DukeEnergyIndianaMemberhttp://www.sec.gov/CIK0001326160duration2013-01-01T00:00:002013-06-30T00:00:00falsefalseDuke Energy Indiana [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiduk_DukeEnergyIndianaMemberdei_LegalEntityAxisexplicitMembernanafalse0Duke Energy Indiana [Member]9true 3duk_PolicyTextBlockLineItemsduk_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Policy Text Block [Line Items]10false 4us-gaap_RevenueRecognitionPolicyTextBlockus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00Additionally, Duke Energy Ohio and Duke Energy Indiana sell, on a revolving basis, nearly all of their retail and wholesale accounts receivable to Cinergy Receivables Company, LLC (CRC). These transfers meet sales/derecognition criteria and, therefore, Duke Energy Ohio and Duke Energy Indiana account for the transfers of receivables to CRC as sales. Accordingly, the receivables sold are not reflected on the Condensed Consolidated Balance Sheets of Duke Energy Ohio and Duke Energy Indiana. See Note 11 for further information. Receivables for unbilled revenues related to retail and wholesale accounts receivable at Duke Energy Ohio and Duke Energy Indiana included in the sales of accounts receivable to CRC were as shown in the table below.falsefalsefalsenonnum:textBlockItemTypenaDisclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18726-107790 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 13 -Section B -Paragraph Question 1 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 13.B.Q1) -URI http://asc.fasb.org/extlink&oid=6600647&loc=d3e214044-122780 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 22 -Paragraph 8, 12, 13 -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 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18823-107790 false0Unbilled RevenuefalseOrganization and Basis of Presentation (Policy)UnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.duke-energy.com/role/OrganizationAndBasisOfPresentationPolicy110