v3.3.0.814

Fair Value Measurements (Quantitative Level 3 Fair Value Disclosure) (Details) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2015 USD ($) $ / MWh | Dec. 31, 2014 USD ($) $ / MWh $ / MMBTU $ / MW
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) | $ 17 | $ (1)
Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) |  | $ (5)
Commodity Natural Gas Hedges [Member] | Minimum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair Value Inputs Price Per MMBtu | $ / MMBTU |  | 2.12
Commodity Natural Gas Hedges [Member] | Maximum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair Value Inputs Price Per MMBtu | $ / MMBTU |  | 4.35
Derivative Financial Instruments Liabilities Power Sale Agreements [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) | $ 1 |
Derivative Financial Instruments Liabilities Power Sale Agreements [Member] | Minimum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh | 18.50 |
Derivative Financial Instruments Liabilities Power Sale Agreements [Member] | Maximum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh | 84.35 |
Financial Transmission Rights [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) | $ 16 | $ 14
Financial Transmission Rights [Member] | Minimum [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh | (0.81) | (1.92)
Financial Transmission Rights [Member] | Maximum [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh | 7.23 | 9.86
Commodity Power Contracts [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) |  | $ (1)
Commodity Power Contracts [Member] | Minimum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh |  | 25.16
Commodity Power Contracts [Member] | Maximum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh |  | 51.75
Commodity Capacity Option Contracts [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) |  | $ 2
Commodity Capacity Option Contracts [Member] | Minimum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair Value Inputs Price Per MW day | $ / MW |  | 21.00
Commodity Capacity Option Contracts [Member] | Maximum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair Value Inputs Price Per MW day | $ / MW |  | 109.00
Derivative Financial Instruments Liabilities Reserves [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) |  | $ (11)
Duke Energy Ohio [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) |  | (18)
Duke Energy Ohio [Member] | Commodity Natural Gas Hedges [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) |  | $ (5)
Duke Energy Ohio [Member] | Commodity Natural Gas Hedges [Member] | Minimum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair Value Inputs Price Per MMBtu | $ / MMBTU |  | 2.12
Duke Energy Ohio [Member] | Commodity Natural Gas Hedges [Member] | Maximum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair Value Inputs Price Per MMBtu | $ / MMBTU |  | 4.35
Duke Energy Ohio [Member] | Financial Transmission Rights [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) | $ 4 |
Duke Energy Ohio [Member] | Financial Transmission Rights [Member] | Minimum [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh | 0.37 |
Duke Energy Ohio [Member] | Financial Transmission Rights [Member] | Maximum [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh | 2.17 |
Duke Energy Ohio [Member] | Commodity Power Contracts [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) |  | $ (6)
Duke Energy Ohio [Member] | Commodity Power Contracts [Member] | Minimum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh |  | 25.25
Duke Energy Ohio [Member] | Commodity Power Contracts [Member] | Maximum [Member] | Discounted Cash Flow [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh |  | 51.75
Duke Energy Ohio [Member] | Derivative Financial Instruments Liabilities Reserves [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) |  | $ (7)
Duke Energy Indiana [Member] | Financial Transmission Rights [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Net derivative asset (liability) | $ 12 | $ 14
Duke Energy Indiana [Member] | Financial Transmission Rights [Member] | Minimum [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh | (0.81) | (1.92)
Duke Energy Indiana [Member] | Financial Transmission Rights [Member] | Maximum [Member] | RTO Auction Pricing [Member] |  |
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |
Fair value inputs, price per MWh | $ / MWh | 7.23 | 9.86

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