Fair Value Measurements (Details 4) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 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	$ 1,751	$ 1,974	$ 2,133	$ 3,678
Realized gains	81	98	118	220
Realized losses	(32)	(38)	(67)	(83)
Interest and dividend income	18	20	51	72
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	1,059	1,100	1,167	1,613
Realized gains	60	52	85	74
Realized losses	(23)	(19)	(48)	(42)
Interest and dividend income	10	9	27	41
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	0	134	57	154
Realized gains	0	7	0	7
Realized losses	0	(1)	0	(1)
Interest and dividend income	1	1	2	3
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	211	234	376	610
Realized gains	6	11	8	37
Realized losses	(2)	(4)	(4)	(10)
Interest and dividend income	$ 4	$ 5	$ 11	$ 13