v2.4.0.8

Fair Value Measurements (Quantitative Level 3 Fair Value Disclosure) (Details) (USD $) In Millions, unless otherwise specified |  |  |  |  |  |  |  |  | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended |  | 12 Months Ended |  |  | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended |  |  | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended |  |  | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |  |  | 12 Months Ended |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended |  |  | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |  |  |  |  |  |  |  | 9 Months Ended | 12 Months Ended | 9 Months Ended | 12 Months Ended
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Sep. 30, 2014 | Jun. 30, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2014 Commodity Natural Gas Hedges [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Natural Gas Hedges [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Commodity Natural Gas Hedges [Member] Minimum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Natural Gas Hedges [Member] Minimum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Commodity Natural Gas Hedges [Member] Maximum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Natural Gas Hedges [Member] Maximum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 FERC Mitigation Power Sale Agreements [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 FERC Mitigation Power Sale Agreements [Member] Minimum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 FERC Mitigation Power Sale Agreements [Member] Maximum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Financial Transmission Rights [Member] RTO Auction Pricing [Member] | Dec. 31, 2013 Financial Transmission Rights [Member] RTO Auction Pricing [Member] | Sep. 30, 2014 Financial Transmission Rights [Member] Minimum [Member] RTO Auction Pricing [Member] | Dec. 31, 2013 Financial Transmission Rights [Member] Minimum [Member] RTO Auction Pricing [Member] | Sep. 30, 2014 Financial Transmission Rights [Member] Maximum [Member] RTO Auction Pricing [Member] | Dec. 31, 2013 Financial Transmission Rights [Member] Maximum [Member] RTO Auction Pricing [Member] | Sep. 30, 2014 Commodity Power Contracts [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Power Contracts [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Commodity Power Contracts [Member] Minimum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Power Contracts [Member] Minimum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Commodity Power Contracts [Member] Maximum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Power Contracts [Member] Maximum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Commodity Capacity Option Contracts [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Capacity Option Contracts [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Commodity Capacity Option Contracts [Member] Minimum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Capacity Option Contracts [Member] Minimum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Commodity Capacity Option Contracts [Member] Maximum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Commodity Capacity Option Contracts [Member] Maximum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Derivative Financial Instruments Liabilities Reserves [Member] | Dec. 31, 2013 Derivative Financial Instruments Liabilities Reserves [Member] | Sep. 30, 2014 Duke Energy Carolinas [Member] | Jun. 30, 2014 Duke Energy Carolinas [Member] | Dec. 31, 2013 Duke Energy Carolinas [Member] | Sep. 30, 2013 Duke Energy Carolinas [Member] | Jun. 30, 2013 Duke Energy Carolinas [Member] | Dec. 31, 2012 Duke Energy Carolinas [Member] | Dec. 31, 2013 Duke Energy Carolinas [Member] FERC Mitigation Power Sale Agreements [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Duke Energy Carolinas [Member] FERC Mitigation Power Sale Agreements [Member] Minimum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Duke Energy Carolinas [Member] FERC Mitigation Power Sale Agreements [Member] Maximum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Progress Energy [Member] | Jun. 30, 2014 Progress Energy [Member] | Dec. 31, 2013 Progress Energy [Member] | Sep. 30, 2013 Progress Energy [Member] | Jun. 30, 2013 Progress Energy [Member] | Dec. 31, 2012 Progress Energy [Member] | Sep. 30, 2014 Duke Energy Progress [Member] | Jun. 30, 2014 Duke Energy Progress [Member] | Dec. 31, 2013 Duke Energy Progress [Member] | Sep. 30, 2013 Duke Energy Progress [Member] | Jun. 30, 2013 Duke Energy Progress [Member] | Dec. 31, 2012 Duke Energy Progress [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] | Jun. 30, 2014 Duke Energy Ohio [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] | Sep. 30, 2013 Duke Energy Ohio [Member] | Jun. 30, 2013 Duke Energy Ohio [Member] | Dec. 31, 2012 Duke Energy Ohio [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] Commodity Natural Gas Hedges [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] Commodity Natural Gas Hedges [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] Commodity Natural Gas Hedges [Member] Minimum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] Commodity Natural Gas Hedges [Member] Minimum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] Commodity Natural Gas Hedges [Member] Maximum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] Commodity Natural Gas Hedges [Member] Maximum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] Commodity Power Contracts [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] Commodity Power Contracts [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] Commodity Power Contracts [Member] Minimum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] Commodity Power Contracts [Member] Minimum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] Commodity Power Contracts [Member] Maximum [Member] Discounted Cash Flow [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] Commodity Power Contracts [Member] Maximum [Member] Discounted Cash Flow [Member] | Sep. 30, 2014 Duke Energy Ohio [Member] Derivative Financial Instruments Liabilities Reserves [Member] | Dec. 31, 2013 Duke Energy Ohio [Member] Derivative Financial Instruments Liabilities Reserves [Member] | Sep. 30, 2014 Duke Energy Indiana [Member] | Jun. 30, 2014 Duke Energy Indiana [Member] | Dec. 31, 2013 Duke Energy Indiana [Member] | Sep. 30, 2013 Duke Energy Indiana [Member] | Jun. 30, 2013 Duke Energy Indiana [Member] | Dec. 31, 2012 Duke Energy Indiana [Member] | Sep. 30, 2014 Duke Energy Indiana [Member] Financial Transmission Rights [Member] RTO Auction Pricing [Member] | Dec. 31, 2013 Duke Energy Indiana [Member] Financial Transmission Rights [Member] RTO Auction Pricing [Member] | Sep. 30, 2014 Duke Energy Indiana [Member] Financial Transmission Rights [Member] Minimum [Member] RTO Auction Pricing [Member] | Dec. 31, 2013 Duke Energy Indiana [Member] Financial Transmission Rights [Member] Minimum [Member] RTO Auction Pricing [Member] | Sep. 30, 2014 Duke Energy Indiana [Member] Financial Transmission Rights [Member] Maximum [Member] RTO Auction Pricing [Member] | Dec. 31, 2013 Duke Energy Indiana [Member] Financial Transmission Rights [Member] Maximum [Member] RTO Auction Pricing [Member]
Net Derivative Asset (Liability) Fair Value Inputs [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net derivative asset (liability) | $ (22) | $ 22 | $ 13 | $ (38) | $ (87) | $ (85) | $ (33) | $ (2) |  |  |  |  | $ (2) |  |  | $ 22 | $ 12 |  |  |  |  | $ (2) | $ 23 |  |  |  |  | $ 5 | $ 4 |  |  |  |  | $ (14) | $ (22) |  | $ (3) | $ (2) | $ (4) | $ (4) | $ (12) | $ (2) |  |  |  |  |  |  | $ (35) | $ (38) |  |  |  |  | $ (35) | $ (38) | $ (55) | $ (28) | $ (4) | $ (6) | $ (19) | $ (6) | $ (33) | $ (2) |  |  |  |  | $ (10) | $ 18 |  |  |  |  | $ (12) | $ (20) | $ 22 | $ 45 | $ 12 | $ 14 | $ 18 | $ 10 | $ 22 | $ 12 |  |  |  |
Fair Value Inputs Price Per MMBtu |  |  |  |  |  |  |  |  | 2.45 | 3.07 | 4.66 | 5.37 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.45 | 3.07 | 4.66 | 5.37 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value inputs, price per MWh |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.79 | 52.38 |  |  | (2.47) | (0.30) | 12.92 | 13.80 |  |  | 25.18 | 20.77 | 59.17 | 58.90 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.79 | 52.38 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.35 | 20.77 | 59.60 | 58.90 |  |  |  |  |  |  |  |  |  |  | (2.47) | (0.30) | 12.92 | 13.80
Fair Value Inputs Price Per MW day |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 28.60 | 30.40 | 189.25 | 165.10 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Price per MMBtu, used as an input to measure fair value for power sale agreements. + References No definition available. + Details
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- Definition Price per MW day, used as an input to measure fair value for power sale agreements. + References No definition available. + Details
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- Definition Price per MWh, used as an input to measure fair value for power sale agreements. + References No definition available. + Details
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- Definition Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19279-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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