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Asset Retirement Obligations (ARO Rollforward) (Details) $ in Millions | 9 Months Ended
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Sep. 30, 2015 USD ($)
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |
Balance at beginning of period | $ 8,466
Acquisitions | 213
Accretion expense | 278
Liabilities settled | (274)
Liabilities incurred in the current year | 983
Revision in estimates of cash flows | 47
Balance at end of period | 9,713
Duke Energy Carolinas [Member] |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |
Balance at beginning of period | 3,428
Accretion expense | 123
Liabilities settled | (107)
Liabilities incurred in the current year | 178
Revision in estimates of cash flows | (23)
Balance at end of period | 3,599
Progress Energy [Member] |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |
Balance at beginning of period | 4,711
Acquisitions | 204
Accretion expense | 150
Liabilities settled | (153)
Liabilities incurred in the current year | 270
Revision in estimates of cash flows | 40
Balance at end of period | 5,222
Duke Energy Progress [Member] |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |
Balance at beginning of period | 3,905
Acquisitions | 204
Accretion expense | 123
Liabilities settled | (53)
Liabilities incurred in the current year | 270
Revision in estimates of cash flows | 40
Balance at end of period | 4,489
Duke Energy Florida [Member] |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |
Balance at beginning of period | 806
Accretion expense | 26
Liabilities settled | (100)
Balance at end of period | 732
Duke Energy Ohio [Member] |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |
Balance at beginning of period | 27
Accretion expense | 2
Liabilities settled | (2)
Liabilities incurred in the current year | 116
Balance at end of period | 143
Duke Energy Indiana [Member] |
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] |
Balance at beginning of period | 32
Accretion expense | 11
Liabilities settled | (12)
Liabilities incurred in the current year | 418
Balance at end of period | $ 449

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- Definition Asset Retirement Obligations Acquired From Acquisition Of Business + References No definition available. + Details
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- Definition The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Asset Retirement Obligation -URI http://asc.fasb.org/extlink&oid=6505190 + Details
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- Definition Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848 + Details
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- Definition Amount of asset retirement obligations incurred during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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- Definition Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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- Definition Amount of the Increase or Decrease in the amount of the asset retirement obligation during the current period for changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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