Variable Interest Entities (Details) (USD $) In Millions	Sep. 30, 2011
FES
Net exposure to loss based upon the casualty value provisions
Maximum Exposure	$ 1,370
Discounted Lease Payments, net	1,176	[1]
Variable Interest Entities Net Exposure	194
OE
Net exposure to loss based upon the casualty value provisions
Maximum Exposure	613
Discounted Lease Payments, net	455	[1]
Variable Interest Entities Net Exposure	158
CEI
Net exposure to loss based upon the casualty value provisions
Maximum Exposure	591	[2]
Discounted Lease Payments, net	70	[1],[2]
Variable Interest Entities Net Exposure	521	[2]
TE
Net exposure to loss based upon the casualty value provisions
Maximum Exposure	591	[2]
Discounted Lease Payments, net	309	[1],[2]
Variable Interest Entities Net Exposure	$ 282	[2]

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

[2] CEI and TE are jointly and severally liable for the maximum loss amounts under certain sale-leaseback agreements