Fair Value Measurements (Details Textuals) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Fair Value of Financial Instruments [Line Items]
Investment excludes Receivables, Payables and Accrued income	$ 2	$ (52)
Cash balance excluded from available for sale securities	160	164
Investments not required to be disclosed	689	693
FES
Fair Value of Financial Instruments [Line Items]
Investment excludes Receivables, Payables and Accrued income	2	(58)
Cash balance excluded from available for sale securities	68	74
OE
Fair Value of Financial Instruments [Line Items]
Investment excludes Receivables, Payables and Accrued income	1	1
Cash balance excluded from available for sale securities	4	2
JCP&L
Fair Value of Financial Instruments [Line Items]
Investment excludes Receivables, Payables and Accrued income		2
Cash balance excluded from available for sale securities	$ 19	$ 19