v3.3.0.814

Debt and Credit Facilities (Summary of Debt Issuances) (Details) - USD ($) $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Dec. 31, 2015 | Sep. 30, 2015
Debt Instrument [Line Items] |  |
Debt issuances |  | $ 1,700
March 2015 3.750% First Mortgage Bond maturing June 2045 [Member] | First Mortgage Bonds [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of debt |  | $ 500
Interest rate |  | 3.75%
Debt issuances |  | $ 500
August 2015 3.250% First Mortgage Bond maturing August 2025 [Member] | First Mortgage Bonds [Member] |  |
Debt Instrument [Line Items] |  |
Interest rate |  | 3.25%
Debt issuances |  | $ 500
August 2015 3.250% First Mortgage Bond maturing August 2025 [Member] | First Mortgage Bonds [Member] | Scenario, Forecast [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of debt | $ 400 |
August 2015 4.200% First Mortgage Bond maturing August 2045 [Member] | First Mortgage Bonds [Member] |  |
Debt Instrument [Line Items] |  |
Interest rate |  | 4.20%
Debt issuances |  | $ 700
August 2015 4.200% First Mortgage Bond maturing August 2045 [Member] | First Mortgage Bonds [Member] | Scenario, Forecast [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of debt | 400 |
Duke Energy Carolinas [Member] |  |
Debt Instrument [Line Items] |  |
Debt issuances |  | 500
Duke Energy Carolinas [Member] | March 2015 3.750% First Mortgage Bond maturing June 2045 [Member] | First Mortgage Bonds [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of debt |  | $ 500
Interest rate |  | 3.75%
Debt issuances |  | $ 500
Duke Energy Progress [Member] |  |
Debt Instrument [Line Items] |  |
Debt issuances |  | $ 1,200
Duke Energy Progress [Member] | August 2015 3.250% First Mortgage Bond maturing August 2025 [Member] | First Mortgage Bonds [Member] |  |
Debt Instrument [Line Items] |  |
Interest rate |  | 3.25%
Debt issuances |  | $ 500
Duke Energy Progress [Member] | August 2015 3.250% First Mortgage Bond maturing August 2025 [Member] | First Mortgage Bonds [Member] | Scenario, Forecast [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of debt | 400 |
Duke Energy Progress [Member] | August 2015 4.200% First Mortgage Bond maturing August 2045 [Member] | First Mortgage Bonds [Member] |  |
Debt Instrument [Line Items] |  |
Interest rate |  | 4.20%
Debt issuances |  | $ 700
Duke Energy Progress [Member] | August 2015 4.200% First Mortgage Bond maturing August 2045 [Member] | First Mortgage Bonds [Member] | Scenario, Forecast [Member] |  |
Debt Instrument [Line Items] |  |
Repayments of debt | $ 400 |

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: 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
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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