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Fair Value Measurements (Fair Value Measurement Amounts for Assets and Liabilities) (Details) - USD ($) $ in Millions | Jun. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | $ 2,272 |
Derivative assets | 87 | $ 51
Total assets | 7,587 | 7,503
Derivative liabilities | (213) | (230)
Net assets (liabilities) | 7,374 | 7,273
Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 3 | 3
Total assets | 5,676 | 5,658
Derivative liabilities | (1) | (2)
Net assets (liabilities) | 5,675 | 5,656
Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 31 | 20
Total assets | 1,788 | 1,743
Derivative liabilities | (62) | (86)
Net assets (liabilities) | 1,726 | 1,657
Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 53 | 28
Total assets | 53 | 28
Derivative liabilities | (150) | (142)
Net assets (liabilities) | (97) | (114)
Fair Value Measured at Net Asset Value Per Share [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 70 | 74
Net assets (liabilities) | 70 | 74
Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 4,988 |
Debt Securities, Available-for-sale | 2,136 |
Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 4,918 |
Debt Securities, Available-for-sale | 578 |
Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 1,558 |
Ndtf [Member] | Fair Value Measured at Net Asset Value Per Share [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 70 |
Investments, Fair Value Disclosure |  | 74
Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 109 |
Debt Securities, Available-for-sale | 267 |
Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 109 |
Debt Securities, Available-for-sale | 68 |
Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 199 |
Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 4,914
Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 4,840
Equity Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 123
Equity Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 123
Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 2,174
Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 635
Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 1,539
Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 241
Debt Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 57
Debt Securities [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 184
Duke Energy Carolinas [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 1,017 |
Derivative assets | 3 | 2
Total assets | 3,784 | 3,760
Derivative liabilities | (19) | (35)
Net assets (liabilities) | 3,765 | 3,725
Duke Energy Carolinas [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 0 |
Total assets | 2,826 | 2,822
Derivative liabilities | 0 | (1)
Net assets (liabilities) | 2,826 | 2,821
Duke Energy Carolinas [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 3 | 2
Total assets | 888 | 864
Derivative liabilities | (19) | (34)
Net assets (liabilities) | 869 | 830
Duke Energy Carolinas [Member] | Fair Value Measured at Net Asset Value Per Share [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 70 | 74
Net assets (liabilities) | 70 | 74
Duke Energy Carolinas [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 2,732 |
Debt Securities, Available-for-sale | 1,049 |
Duke Energy Carolinas [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 2,662 |
Debt Securities, Available-for-sale | 164 |
Duke Energy Carolinas [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 885 |
Duke Energy Carolinas [Member] | Ndtf [Member] | Fair Value Measured at Net Asset Value Per Share [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 70 |
Investments, Fair Value Disclosure |  | 74
Duke Energy Carolinas [Member] | Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 2,692
Duke Energy Carolinas [Member] | Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 2,618
Duke Energy Carolinas [Member] | Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 1,066
Duke Energy Carolinas [Member] | Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 204
Duke Energy Carolinas [Member] | Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 862
Progress Energy [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 1,050 |
Derivative assets | 5 | 3
Total assets | 3,406 | 3,392
Derivative liabilities | (35) | (36)
Net assets (liabilities) | 3,371 | 3,356
Progress Energy [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 0 | 1
Total assets | 2,681 | 2,666
Derivative liabilities | 0 | (1)
Net assets (liabilities) | 2,681 | 2,665
Progress Energy [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 5 | 2
Total assets | 725 | 726
Derivative liabilities | (35) | (35)
Net assets (liabilities) | 690 | 691
Progress Energy [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 2,256 |
Debt Securities, Available-for-sale | 1,087 |
Progress Energy [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 2,256 |
Debt Securities, Available-for-sale | 414 |
Progress Energy [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 673 |
Progress Energy [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 58 |
Progress Energy [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 11 |
Progress Energy [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 47 |
Progress Energy [Member] | Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 2,222
Progress Energy [Member] | Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 2,222
Progress Energy [Member] | Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 1,108
Progress Energy [Member] | Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 431
Progress Energy [Member] | Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 677
Progress Energy [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 59
Progress Energy [Member] | Debt Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 12
Progress Energy [Member] | Debt Securities [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 47
Duke Energy Progress [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 762 |
Derivative assets | 4 | 2
Total assets | 2,632 | 2,594
Derivative liabilities | (21) | (18)
Net assets (liabilities) | 2,611 | 2,576
Duke Energy Progress [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 1 | 1
Total assets | 2,076 | 2,040
Derivative liabilities | 0 | (1)
Net assets (liabilities) | 2,076 | 2,039
Duke Energy Progress [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 3 | 1
Total assets | 556 | 554
Derivative liabilities | (21) | (17)
Net assets (liabilities) | 535 | 537
Duke Energy Progress [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 1,819 |
Debt Securities, Available-for-sale | 808 |
Duke Energy Progress [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 1,819 |
Debt Securities, Available-for-sale | 255 |
Duke Energy Progress [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 553 |
Duke Energy Progress [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 1 |
Duke Energy Progress [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 1 |
Duke Energy Progress [Member] | Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 1,795
Duke Energy Progress [Member] | Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 1,795
Duke Energy Progress [Member] | Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 796
Duke Energy Progress [Member] | Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 243
Duke Energy Progress [Member] | Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 553
Duke Energy Progress [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 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, Fair Value Disclosure |  | 1
Duke Energy Florida [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 288 |
Derivative assets | 1 | 1
Total assets | 765 | 788
Derivative liabilities | (5) | (12)
Net assets (liabilities) | 760 | 776
Duke Energy Florida [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 597 | 616
Net assets (liabilities) | 597 | 616
Duke Energy Florida [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 1 | 1
Total assets | 168 | 172
Derivative liabilities | (5) | (12)
Net assets (liabilities) | 163 | 160
Duke Energy Florida [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 437 |
Debt Securities, Available-for-sale | 279 |
Duke Energy Florida [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 437 |
Debt Securities, Available-for-sale | 159 |
Duke Energy Florida [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 120 |
Duke Energy Florida [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 48 |
Duke Energy Florida [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 1 |
Duke Energy Florida [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 47 |
Duke Energy Florida [Member] | Equity Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 427
Duke Energy Florida [Member] | Equity Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 427
Duke Energy Florida [Member] | Debt Securities [Member] | Ndtf [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 312
Duke Energy Florida [Member] | Debt Securities [Member] | Ndtf [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 188
Duke Energy Florida [Member] | Debt Securities [Member] | Ndtf [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 124
Duke Energy Florida [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 48
Duke Energy Florida [Member] | Debt Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 1
Duke Energy Florida [Member] | Debt Securities [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 47
Duke Energy Ohio [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 9 | 1
Derivative liabilities | (4) | (5)
Net assets (liabilities) | 5 | (4)
Duke Energy Ohio [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative liabilities | (4) | (5)
Net assets (liabilities) | (4) | (5)
Duke Energy Ohio [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 9 | 1
Net assets (liabilities) | 9 | 1
Duke Energy Indiana [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 74 |
Debt Securities, Available-for-sale | 41 |
Derivative assets | 45 | 27
Total assets | 160 | 155
Duke Energy Indiana [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 1 |
Total assets | 75 | 97
Duke Energy Indiana [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total assets | 41 | 31
Duke Energy Indiana [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 44 | 27
Total assets | 44 | 27
Duke Energy Indiana [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 74 |
Debt Securities, Available-for-sale | 41 |
Duke Energy Indiana [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Equity Securities, FV-NI | 74 |
Duke Energy Indiana [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt Securities, Available-for-sale | 41 |
Duke Energy Indiana [Member] | Equity Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 97
Duke Energy Indiana [Member] | Equity Securities [Member] | Other Classification [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 97
Duke Energy Indiana [Member] | Debt Securities [Member] | Other Classification [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 31
Duke Energy Indiana [Member] | Debt Securities [Member] | Other Classification [Member] | Level 2 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 31
Piedmont Natural Gas [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 2 | 2
Total assets |  | 3
Derivative liabilities | (150) | (142)
Net assets (liabilities) | (148) | (139)
Piedmont Natural Gas [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative assets | 2 | 2
Total assets |  | 3
Net assets (liabilities) | 2 | 3
Piedmont Natural Gas [Member] | Level 3 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Derivative liabilities | (150) | (142)
Net assets (liabilities) | $ (150) | (142)
Piedmont Natural Gas [Member] | Debt Securities [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | 1
Piedmont Natural Gas [Member] | Debt Securities [Member] | Level 1 [Member] |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investments, Fair Value Disclosure |  | $ 1

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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- Definition Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
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