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