Derivative Instruments (Details 2) MWh in Millions, MMBTU in Millions	Mar. 31, 2016 MMBTU MWh
Power Contracts
Volume of First Energy's outstanding derivative transactions
Purchases (in MWH or mmBTUs)	14
Sales (in MWH or mmBTUs)	42
Net (in MWH or mmBTUs)	(28)
FTRs
Volume of First Energy's outstanding derivative transactions
Purchases (in MWH or mmBTUs)	15
Sales (in MWH or mmBTUs)	0
Net (in MWH or mmBTUs)	15
NUGs
Volume of First Energy's outstanding derivative transactions
Purchases (in MWH or mmBTUs)	4
Sales (in MWH or mmBTUs)	0
Net (in MWH or mmBTUs)	4
Natural Gas
Volume of First Energy's outstanding derivative transactions
Purchases (in MWH or mmBTUs) | MMBTU	81
Sales (in MWH or mmBTUs) | MMBTU	1
Net (in MWH or mmBTUs) | MMBTU	80