Variable Interest Entities (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012
FES
Net exposure to loss based upon the casualty value provisions
Maximum Exposure	$ 1,384
Discounted Lease Payments, net	1,179	[1]
Variable Interest Entities Net Exposure	205
OE
Net exposure to loss based upon the casualty value provisions
Maximum Exposure	583
Discounted Lease Payments, net	426	[1]
Variable Interest Entities Net Exposure	157
Other First Energy Subsidiaries
Net exposure to loss based upon the casualty value provisions
Maximum Exposure	643
Discounted Lease Payments, net	383	[1]
Variable Interest Entities Net Exposure	$ 260

[1] The net present value of FirstEnergy’s consolidated sale and leaseback operating lease commitments is $1.6 billion.