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Asset Sales and Impairments (Details 2) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items] |  |
Impairment |  | $ 42
FES |  |
Finite-Lived Intangible Assets [Line Items] |  |
Impairment | $ 2,045 | $ 33
FES | Nuclear generation assets | Beaver Valley |  |
Finite-Lived Intangible Assets [Line Items] |  |
Impairment | 107 |
FES | Nuclear generation assets | Davis Besse |  |
Finite-Lived Intangible Assets [Line Items] |  |
Impairment | 420 |
FES | Nuclear generation assets | Perry |  |
Finite-Lived Intangible Assets [Line Items] |  |
Impairment | 124 |
FES | Nuclear Fuel |  |
Finite-Lived Intangible Assets [Line Items] |  |
Impairment | 369 |
FES | Materials and Supplies |  |
Finite-Lived Intangible Assets [Line Items] |  |
Impairment | 81 |
FES | Asset retirement obligation |  |
Finite-Lived Intangible Assets [Line Items] |  |
Impairment | $ 944 |

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