Fair Value Measurements (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Proceeds from the sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income
Sales Proceeds	$ 251	$ 969
Realized gains	19	100
Realized losses	(17)	(29)
Interest and dividend income	15	24
FES
Proceeds from the sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income
Sales Proceeds	83	216
Realized gains	12	12
Realized losses	(11)	(15)
Interest and dividend income	7	15
OE
Proceeds from the sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income
Sales Proceeds	37	8
Realized gains	0	0
Realized losses	0	0
Interest and dividend income	1	1
JCP&L
Proceeds from the sale of investments in available-for-sale securities, realized gains and losses on those sales, and interest and dividend income
Sales Proceeds	95	217
Realized gains	1	22
Realized losses	(1)	(4)
Interest and dividend income	$ 4	$ 4