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Asset Retirement Obligations (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Sep. 30, 2017 | Dec. 31, 2016
FES | Beaver Valley, Davis-Besse and Perry Power Plants |  |  |  |
Asset Retirement Obligations [Line Items] |  |  |  |
Asset retirement obligation |  |  | $ 800 | $ 713
FES | Beaver Valley Unit 2 |  |  |  |
Asset Retirement Obligations [Line Items] |  |  |  |
ARO transferred | $ 73 |  |  |
FES | Perry Power Plant Unit 1 |  |  |  |
Asset Retirement Obligations [Line Items] |  |  |  |
ARO transferred |  | $ 28 |  |
NG | Beaver Valley Unit 2 |  |  |  |
Asset Retirement Obligations [Line Items] |  |  |  |
ARO transferred | $ 49 |  |  |

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- Definition Asset Retirement Obligations. + References No definition available. + Details
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- Definition Asset Retirement Obligations, Transfers + 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 + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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