Taxes (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
FE
Accumulated deferred income taxes
Property basis differences	$ 6,738	$ 3,910
Regulatory transition charge	105	235
Customer receivables for future income taxes	125	113
Deferred MISO/PJM transmission costs	51	85
Other regulatory assets - RCP	165	166
Deferred sale and leaseback gain	(450)	(469)
Nonutility generation costs	36	51
Unamortized investment tax credits	(72)	(44)
Unrealized losses on derivative hedges	(21)	(29)
Pensions and OPEB	(752)	(686)
Lease market valuation liability	(179)	(197)
Oyster Creek securitization (Note 12)	93	109
Nuclear decommissioning activities	123	47
Mark-to-market adjustments	(7)	(42)
Deferred gain for asset sales - affiliated companies	0	0
Equity investments	132
Loss carryforwards and AMT credits	(612)
Loss carryforwards		(41)
Loss carryforward valuation reserve	34	26
All other	161	(74)
Net deferred income tax liability (asset)	5,670	3,160
FES
Accumulated deferred income taxes
Property basis differences	770	650
Regulatory transition charge	0	12
Customer receivables for future income taxes	0	0
Deferred MISO/PJM transmission costs	0	0
Other regulatory assets - RCP	0	0
Deferred sale and leaseback gain	(398)	(412)
Nonutility generation costs	0	0
Unamortized investment tax credits	(19)	(20)
Unrealized losses on derivative hedges	5	0
Pensions and OPEB	(85)	(96)
Lease market valuation liability	(65)	(82)
Oyster Creek securitization (Note 12)	0	0
Nuclear decommissioning activities	108	79
Mark-to-market adjustments	(7)	(42)
Deferred gain for asset sales - affiliated companies	0	0
Equity investments	0
Loss carryforwards and AMT credits	(34)
Loss carryforwards		(10)
Loss carryforward valuation reserve	12	9
All other	(1)	(21)
Net deferred income tax liability (asset)	286	67
OE
Accumulated deferred income taxes
Property basis differences	673	625
Regulatory transition charge	30	37
Customer receivables for future income taxes	0	0
Deferred MISO/PJM transmission costs	0	0
Other regulatory assets - RCP	82	82
Deferred sale and leaseback gain	(31)	(35)
Nonutility generation costs	0	0
Unamortized investment tax credits	(3)	(4)
Unrealized losses on derivative hedges	0	0
Pensions and OPEB	(76)	(58)
Lease market valuation liability	0	0
Oyster Creek securitization (Note 12)	0	0
Nuclear decommissioning activities	15	7
Mark-to-market adjustments	0	0
Deferred gain for asset sales - affiliated companies	31	34
Equity investments	0
Loss carryforwards and AMT credits	0
Loss carryforwards		0
Loss carryforward valuation reserve	0	0
All other	66	49
Net deferred income tax liability (asset)	787	737
CEI
Accumulated deferred income taxes
Property basis differences	527	496
Regulatory transition charge	73	89
Customer receivables for future income taxes	0	0
Deferred MISO/PJM transmission costs	0	0
Other regulatory assets - RCP	55	56
Deferred sale and leaseback gain	0	0
Nonutility generation costs	0	0
Unamortized investment tax credits	(4)	(4)
Unrealized losses on derivative hedges	0	0
Pensions and OPEB	(36)	(32)
Lease market valuation liability	0	0
Oyster Creek securitization (Note 12)	0	0
Nuclear decommissioning activities	0	(1)
Mark-to-market adjustments	0	0
Deferred gain for asset sales - affiliated companies	20	22
Equity investments	0
Loss carryforwards and AMT credits	0
Loss carryforwards		0
Loss carryforward valuation reserve	0	0
All other	28	21
Net deferred income tax liability (asset)	663	647
TE
Accumulated deferred income taxes
Property basis differences	206	206
Regulatory transition charge	5	3
Customer receivables for future income taxes	0	0
Deferred MISO/PJM transmission costs	0	0
Other regulatory assets - RCP	28	28
Deferred sale and leaseback gain	0	0
Nonutility generation costs	0	0
Unamortized investment tax credits	(2)	(2)
Unrealized losses on derivative hedges	0	0
Pensions and OPEB	(18)	(28)
Lease market valuation liability	(68)	(81)
Oyster Creek securitization (Note 12)	0	0
Nuclear decommissioning activities	17	15
Mark-to-market adjustments	0	0
Deferred gain for asset sales - affiliated companies	7	7
Equity investments	0
Loss carryforwards and AMT credits	0
Loss carryforwards		0
Loss carryforward valuation reserve	0	0
All other	(5)	(7)
Net deferred income tax liability (asset)	170	141
JCP&L
Accumulated deferred income taxes
Property basis differences	792	728
Regulatory transition charge	49	95
Customer receivables for future income taxes	12	13
Deferred MISO/PJM transmission costs	0	0
Other regulatory assets - RCP	0	0
Deferred sale and leaseback gain	(10)	(10)
Nonutility generation costs	(2)	0
Unamortized investment tax credits	(2)	(2)
Unrealized losses on derivative hedges	(1)	0
Pensions and OPEB	(75)	(74)
Lease market valuation liability	0	0
Oyster Creek securitization (Note 12)	93	109
Nuclear decommissioning activities	(7)	(8)
Mark-to-market adjustments	0	0
Deferred gain for asset sales - affiliated companies	0	0
Equity investments	0
Loss carryforwards and AMT credits	0
Loss carryforwards		0
Loss carryforward valuation reserve	0	0
All other	10	(58)
Net deferred income tax liability (asset)	859	793
Met-Ed
Accumulated deferred income taxes
Property basis differences	457	407
Regulatory transition charge	2	(1)
Customer receivables for future income taxes	55	48
Deferred MISO/PJM transmission costs	34	62
Other regulatory assets - RCP	0	0
Deferred sale and leaseback gain	(12)	(12)
Nonutility generation costs	31	55
Unamortized investment tax credits	(4)	(5)
Unrealized losses on derivative hedges	0	0
Pensions and OPEB	(24)	(13)
Lease market valuation liability	0	0
Oyster Creek securitization (Note 12)	0	0
Nuclear decommissioning activities	7	2
Mark-to-market adjustments	0	0
Deferred gain for asset sales - affiliated companies	0	0
Equity investments	0
Loss carryforwards and AMT credits	(6)
Loss carryforwards		0
Loss carryforward valuation reserve	0	0
All other	0	(17)
Net deferred income tax liability (asset)	540	526
Penelec
Accumulated deferred income taxes
Property basis differences	577	504
Regulatory transition charge	0	0
Customer receivables for future income taxes	58	52
Deferred MISO/PJM transmission costs	17	23
Other regulatory assets - RCP	0	0
Deferred sale and leaseback gain	0	0
Nonutility generation costs	7	(4)
Unamortized investment tax credits	(4)	(4)
Unrealized losses on derivative hedges	0	0
Pensions and OPEB	(114)	(80)
Lease market valuation liability	0	0
Oyster Creek securitization (Note 12)	0	0
Nuclear decommissioning activities	(17)	(47)
Mark-to-market adjustments	0	0
Deferred gain for asset sales - affiliated companies	0	0
Equity investments	0
Loss carryforwards and AMT credits	(30)
Loss carryforwards		(23)
Loss carryforward valuation reserve	7	11
All other	(2)	6
Net deferred income tax liability (asset)	$ 499	$ 438