Transactions With Affiliated Companies (Details) - FES T in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) T	Dec. 31, 2015 USD ($) T	Dec. 31, 2014 USD ($) T
Investment Income:
Interest income from FE	$ 2.0	$ 2.0	$ 3.0
Interest Expense:
Interest expense to affiliates	5.0	4.0	3.0
Interest expense to FE	2.0	3.0	4.0
AE Supply
REVENUES:
Revenues	$ 80.4	$ 62.8	$ 96.3
Interest Expense:
Amount of coal sold under purchase agreement (in T) | T	1.5	1.2	1.7
Electric sales to affiliates
REVENUES:
Revenues	$ 457.0	$ 664.0	$ 861.0
Other
REVENUES:
Revenues	11.0	14.0	15.0
Purchased power from affiliates
Expenses:
Expenses	622.0	353.0	271.0
Fuel
Expenses:
Expenses	4.0	1.0	1.0
Support services
Expenses:
Expenses	748.0	705.0	619.0
Pension and OPEB mark-to-market adjustment
Expenses:
Expenses	$ 71.0	$ 76.0	$ 257.0