Taxes (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Accumulated deferred income taxes
Property basis differences	$ 7,868	$ 6,738
Regulatory transition charge	79	105
Customer receivables for future income taxes	130	138
Deferred MISO/PJM transmission costs	125	51
Other regulatory assets - RCP	161	165
Deferred sale and leaseback gain	(431)	(450)
Nonutility generation costs	5	36
Unamortized investment tax credits	(67)	(72)
Unrealized losses on derivative hedges	(21)	(21)
Pensions and OPEB	(1,102)	(752)
Lease market valuation liability	(81)	(179)
Oyster Creek securitization (Note 11)	75	93
Nuclear decommissioning activities	127	123
Mark-to-market adjustments	30	(7)
Deferred gain for asset sales - affiliated companies	0	0
Loss carryforwards and AMT credits	(1,199)	(612)
Loss carryforward valuation reserve	102	34
Storm damage	192	55
Market transition charge	65	17
All other	239	208
Net deferred income tax liability (asset)	6,297	5,670
FES
Accumulated deferred income taxes
Property basis differences	1,060	770
Regulatory transition charge	0	0
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	(384)	(398)
Nonutility generation costs	0	0
Unamortized investment tax credits	(17)	(19)
Unrealized losses on derivative hedges	2	5
Pensions and OPEB	(105)	(85)
Lease market valuation liability	33	(65)
Oyster Creek securitization (Note 11)	0	0
Nuclear decommissioning activities	111	108
Mark-to-market adjustments	30	(7)
Deferred gain for asset sales - affiliated companies	0	0
Loss carryforwards and AMT credits	(221)	(34)
Loss carryforward valuation reserve	16	12
Storm damage	0	0
Market transition charge	0	0
All other	(22)	(1)
Net deferred income tax liability (asset)	503	286
OE
Accumulated deferred income taxes
Property basis differences	728	673
Regulatory transition charge	5	30
Customer receivables for future income taxes	9	13
Deferred MISO/PJM transmission costs	0	0
Other regulatory assets - RCP	80	82
Deferred sale and leaseback gain	(26)	(31)
Nonutility generation costs	0	0
Unamortized investment tax credits	(3)	(3)
Unrealized losses on derivative hedges	0	0
Pensions and OPEB	(108)	(76)
Lease market valuation liability	0	0
Oyster Creek securitization (Note 11)	0	0
Nuclear decommissioning activities	15	15
Mark-to-market adjustments	0	0
Deferred gain for asset sales - affiliated companies	27	31
Loss carryforwards and AMT credits	0	0
Loss carryforward valuation reserve	0	0
Storm damage	0	0
Market transition charge	0	0
All other	40	53
Net deferred income tax liability (asset)	767	787
JCP&L
Accumulated deferred income taxes
Property basis differences	919	792
Regulatory transition charge	44	49
Customer receivables for future income taxes	1	12
Deferred MISO/PJM transmission costs	0	0
Other regulatory assets - RCP	0	0
Deferred sale and leaseback gain	(9)	(10)
Nonutility generation costs	(22)	(2)
Unamortized investment tax credits	(2)	(2)
Unrealized losses on derivative hedges	(1)	(1)
Pensions and OPEB	(106)	(75)
Lease market valuation liability	0	0
Oyster Creek securitization (Note 11)	75	93
Nuclear decommissioning activities	(22)	(7)
Mark-to-market adjustments	0	0
Deferred gain for asset sales - affiliated companies	0	0
Loss carryforwards and AMT credits	(21)	0
Loss carryforward valuation reserve	0	0
Storm damage	163	42
Market transition charge	65	17
All other	4	(49)
Net deferred income tax liability (asset)	$ 1,088	$ 859