v2.4.0.8

Related Party Transactions (Narrative) (Details) (USD $) |  | 9 Months Ended |  |  |  |  |  | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2014 | Sep. 30, 2014 DECAM [Member] | Sep. 30, 2014 Parent Company [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] DECAM [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] DECAM [Member] | Apr. 30, 2014 Unsecured Debt [Member] Parent Company [Member] | Sep. 30, 2014 Unsecured Debt [Member] Duke Energy Ohio [Member] | Sep. 30, 2014 April 2014 0.612% Senior Unsecured Floating Notes Maturing April 2017 [Member] Unsecured Debt [Member] | Sep. 30, 2014 April 2014 0.612% Senior Unsecured Floating Notes Maturing April 2017 [Member] Unsecured Debt [Member] Parent Company [Member]
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Intercompany loan payable |  |  |  | $ 563,000,000 | $ 43,000,000 | $ 550,000,000 | $ 43,000,000 |  |  |  |  |  |
Debt issuances | 2,222,000,000 |  | 1,000,000,000 |  |  |  |  | 1,000,000,000 |  | 400,000,000 | [1] | 400,000,000 | [1]
Proceeds from Issuance of Debt |  | 400,000,000 |  |  |  |  |  |  |  |  |  |  |
Proceeds from (Repayments of) Debt |  |  |  |  |  |  |  |  | $ 402,000,000 |  |  |  |
[1] | Proceeds were used to redeem $402 million of tax-exempt bonds at Duke Energy Ohio, the repayment of outstanding commercial paper and for general corporate purposes. See Note 9 for additional information related to the redemption of Duke Energy Ohio's tax-exempt bonds.

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