v3.3.0.814

Fair Value Measurements (Fair Value Measurement Amounts for Assets and Liabilities) (Details) - USD ($) $ in Millions | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | $ 33 | $ 110
Assets, fair value disclosure | 6,009 | 6,018
Derivative liabilities | (406) | (668)
Net assets, fair value | 5,603 | 5,350
Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets |  | 49
Assets, fair value disclosure | 3,956 | 4,327
Derivative liabilities | (4) | (162)
Net assets, fair value | 3,952 | 4,165
Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 16 | 24
Assets, fair value disclosure | 1,860 | 1,498
Derivative liabilities | (402) | (468)
Net assets, fair value | 1,458 | 1,030
Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 17 | 37
Assets, fair value disclosure | 193 | 193
Derivative liabilities |  | (38)
Net assets, fair value | 193 | 155
Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 3,396 | 3,650
Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 3,224 | 3,493
Equity Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1 | 6
Equity Securities [Member] | Ndtf [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 171 | 151
Equity Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 90 | 96
Equity Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 90 | 96
Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 2,166 | 1,899
Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 557 | 648
Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1,609 | 1,251
Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 324 | 263
Debt Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 85 | 41
Debt Securities [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 234 | 217
Debt Securities [Member] | Other Classification [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 5 | 5
Duke Energy Carolinas [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Assets, fair value disclosure | 2,953 | 3,035
Derivative liabilities | (33) | (19)
Net assets, fair value | 2,920 | 3,016
Duke Energy Carolinas [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Assets, fair value disclosure | 2,021 | 2,143
Net assets, fair value | 2,021 | 2,143
Duke Energy Carolinas [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Assets, fair value disclosure | 758 | 738
Derivative liabilities | (33) | (19)
Net assets, fair value | 725 | 719
Duke Energy Carolinas [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Assets, fair value disclosure | 174 | 154
Net assets, fair value | 174 | 154
Duke Energy Carolinas [Member] | Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1,990 | 2,162
Duke Energy Carolinas [Member] | Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1,818 | 2,005
Duke Energy Carolinas [Member] | Equity Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1 | 6
Duke Energy Carolinas [Member] | Equity Securities [Member] | Ndtf [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 171 | 151
Duke Energy Carolinas [Member] | Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 960 | 870
Duke Energy Carolinas [Member] | Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 203 | 138
Duke Energy Carolinas [Member] | Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 757 | 732
Duke Energy Carolinas [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 3 | 3
Duke Energy Carolinas [Member] | Debt Securities [Member] | Other Classification [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 3 | 3
Progress Energy [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 13 | 4
Assets, fair value disclosure | 2,691 | 2,579
Derivative liabilities | (309) | (373)
Net assets, fair value | 2,382 | 2,206
Progress Energy [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Assets, fair value disclosure | 1,783 | 2,013
Net assets, fair value | 1,783 | 2,013
Progress Energy [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 13 | 4
Assets, fair value disclosure | 908 | 566
Derivative liabilities | (309) | (373)
Net assets, fair value | 599 | 193
Progress Energy [Member] | Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1,406 | 1,488
Progress Energy [Member] | Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1,406 | 1,488
Progress Energy [Member] | Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1,206 | 1,029
Progress Energy [Member] | Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 354 | 510
Progress Energy [Member] | Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 852 | 519
Progress Energy [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 66 | 58
Progress Energy [Member] | Debt Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 23 | 15
Progress Energy [Member] | Debt Securities [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 43 | 43
Duke Energy Progress [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 2 |
Assets, fair value disclosure | 1,946 | 1,711
Derivative liabilities | (95) | (132)
Net assets, fair value | 1,851 | 1,579
Duke Energy Progress [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Assets, fair value disclosure | 1,244 | 1,322
Net assets, fair value | 1,244 | 1,322
Duke Energy Progress [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 2 |
Assets, fair value disclosure | 702 | 389
Derivative liabilities | (95) | (132)
Net assets, fair value | 607 | 257
Duke Energy Progress [Member] | Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1,107 | 1,171
Duke Energy Progress [Member] | Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1,107 | 1,171
Duke Energy Progress [Member] | Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 836 | 540
Duke Energy Progress [Member] | Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 136 | 151
Duke Energy Progress [Member] | Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 700 | 389
Duke Energy Progress [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1 |
Duke Energy Progress [Member] | Debt Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 1 |
Duke Energy Florida [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 11 | 4
Assets, fair value disclosure | 734 | 854
Derivative liabilities | (209) | (241)
Net assets, fair value | 525 | 613
Duke Energy Florida [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Assets, fair value disclosure | 529 | 676
Net assets, fair value | 529 | 676
Duke Energy Florida [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 11 | 4
Assets, fair value disclosure | 205 | 178
Derivative liabilities | (209) | (241)
Net assets, fair value | (4) | (63)
Duke Energy Florida [Member] | Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 299 | 317
Duke Energy Florida [Member] | Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 299 | 317
Duke Energy Florida [Member] | Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 370 | 489
Duke Energy Florida [Member] | Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 219 | 359
Duke Energy Florida [Member] | Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 151 | 130
Duke Energy Florida [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 54 | 44
Duke Energy Florida [Member] | Debt Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 11 |
Duke Energy Florida [Member] | Debt Securities [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments | 43 | 44
Duke Energy Ohio [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 4 | 49
Derivative liabilities | (7) | (181)
Net assets, fair value | (3) | (132)
Duke Energy Ohio [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets |  | 20
Derivative liabilities |  | (117)
Net assets, fair value |  | (97)
Duke Energy Ohio [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets |  | 9
Derivative liabilities | (7) | (26)
Net assets, fair value | (7) | (17)
Duke Energy Ohio [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 4 | 20
Derivative liabilities |  | (38)
Net assets, fair value | 4 | (18)
Duke Energy Indiana [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 12 | 14
Net assets, fair value | 109 | 115
Duke Energy Indiana [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Net assets, fair value | 67 | 71
Duke Energy Indiana [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Net assets, fair value | 30 | 30
Duke Energy Indiana [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 12 | 14
Net assets, fair value | 12 | 14
Duke Energy Indiana [Member] | Equity Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Available-for-sale equity securities | 67 | 71
Duke Energy Indiana [Member] | Equity Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Available-for-sale equity securities | 67 | 71
Duke Energy Indiana [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Available-for-sale debt securities | 30 | 30
Duke Energy Indiana [Member] | Debt Securities [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Available-for-sale debt securities | $ 30 | $ 30

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258 + Details
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- Definition Equity securities categorized neither as held-to-maturity nor trading which are intended be sold more than one year from the balance sheet date or operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26626-111562 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13495-108611 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313 + Details
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27723805&loc=d3e24584-111560 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Available-for-Sale Securities -URI http://asc.fasb.org/extlink&oid=6505594 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph a, f, g -Article 7 + Details
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