Derivative Instruments (Details 1)	Mar. 31, 2012 MWh
Power Contracts
Volume of First Energy's outstanding derivative transactions
Purchases	33,000,000
Sales	47,000,000
Net	(14,000,000)
FTRs
Volume of First Energy's outstanding derivative transactions
Purchases	17,000,000
Sales	0
Net	17,000,000
NUGs
Volume of First Energy's outstanding derivative transactions
Purchases	23,000,000
Sales	0
Net	23,000,000
Natural Gas Futures
Volume of First Energy's outstanding derivative transactions
Purchases	11,000,000
Sales	0
Net	11,000,000