Pension and Other Postretirement Benefits (Details 12) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Pensions
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	$ 807	$ 329	$ 561
Pensions | FES
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	168	122	169
Pensions | OE
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	63	4	38
Pensions | CEI
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	27	10	74
Pensions | TE
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	14	6	26
Pensions | JCP&L
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	68	29	49
Pensions | Met-Ed
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	35	12	29
Pensions | Penelec
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	52	19	76
OPEB
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	(146)	(152)	(119)
OPEB | FES
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	(42)	(12)	0
OPEB | OE
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	(34)	(26)	(30)
OPEB | CEI
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	(18)	(9)	(10)
OPEB | TE
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	(7)	(6)	(2)
OPEB | JCP&L
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	2	(10)	(3)
OPEB | Met-Ed
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	(9)	(24)	(15)
OPEB | Penelec
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net Periodic Pension and OPEB Costs	$ (7)	$ (24)	$ (14)