Supplemental Guarantor Information (Details 1) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
CURRENT ASSETS:
Cash and cash equivalents	$ 109	$ 218	$ 67	$ 172
Receivables-
Customers	1,869	1,720
Other Receivables	218	198
Materials and supplies, at average cost	740	752
Derivatives	247	166
Collateral	580	155
Prepayments and other	199	212
Total current assets	4,577	4,013
PROPERTY, PLANT AND EQUIPMENT:
In service	44,782	44,228
Less - Accumulated provision for depreciation	13,555	13,280
Property, plant and equipment in service net of accumulated provision for depreciation	31,227	30,948
Construction work in progress	2,661	2,304
Total net property, plant and equipment	33,888	33,252
INVESTMENTS:
Nuclear plant decommissioning trusts	2,263	2,201
Other	898	903
Total other property and investments	3,161	3,104
ASSETS HELD FOR SALE	0	235
DEFERRED CHARGES AND OTHER ASSETS:
Goodwill	6,418	6,418	6,447
Other	1,386	1,548
Total deferred charges and other assets	9,602	9,820
Total assets	51,228	50,424	50,424
CURRENT LIABILITIES:
Currently payable long-term debt	1,416	1,415
Accounts payable-
Accrued taxes	527	485
Derivatives	159	111
Other	863	621
Total current liabilities	7,737	7,637
CAPITALIZATION:
Total equity	12,602	12,692
Long-term debt and other long-term obligations	16,804	15,831
Total capitalization	29,409	28,526
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	850	858
Accumulated deferred income taxes	7,028	6,968
Asset retirement obligations	1,704	1,678
Retirement benefits	2,713	2,689
Other	1,532	1,778
Total noncurrent liabilities	14,082	14,261
Total liabilities and capitalization	51,228	50,424
FES
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	583	539
Affiliated companies	278	938
Other Receivables	60	52
Notes receivable from affiliated companies	457	203
Materials and supplies, at average cost	63	76
Derivatives	244	165
Collateral	544	136
Prepayments and other	100	52
Total current assets	2,329	2,161
PROPERTY, PLANT AND EQUIPMENT:
In service	106	104
Less - Accumulated provision for depreciation	30	28
Property, plant and equipment in service net of accumulated provision for depreciation	76	76
Construction work in progress	26	23
Total net property, plant and equipment	102	99
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in affiliated companies	5,891	5,801
Other	0	0
Total other property and investments	5,891	5,801
ASSETS HELD FOR SALE		0
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	0	0
Customer intangibles	91	95
Goodwill	23	23
Property taxes	0	0
Unamortized sale and leaseback costs	0	0
Derivatives	65	53
Other	72	81
Total deferred charges and other assets	251	252
Total assets	8,573	8,313
CURRENT LIABILITIES:
Currently payable long-term debt	1	1
Short-term borrowings	550	0
Accounts payable-
Affiliated companies	373	741
Other	183	94
Accrued taxes	3	204
Derivatives	159	110
Other	51	70
Total current liabilities	1,956	2,197
CAPITALIZATION:
Total equity	5,807	5,312
Long-term debt and other long-term obligations	712	712
Total capitalization	6,519	6,024
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	0	0
Accumulated deferred income taxes	11	32
Asset retirement obligations	0	0
Retirement benefits	22	22
Derivatives	36	14
Other	29	24
Total noncurrent liabilities	98	92
Total liabilities and capitalization	8,573	8,313
FES | Affiliates
CURRENT LIABILITIES:
Short-term borrowings	636	977
FGCO
CURRENT ASSETS:
Cash and cash equivalents	2	2	3	3
Receivables-
Customers	0	0
Affiliated companies	185	787
Other Receivables	18	12
Notes receivable from affiliated companies	449	23
Materials and supplies, at average cost	148	159
Derivatives	0	0
Collateral	0	0
Prepayments and other	79	50
Total current assets	881	1,033
PROPERTY, PLANT AND EQUIPMENT:
In service	6,148	6,105
Less - Accumulated provision for depreciation	1,978	1,953
Property, plant and equipment in service net of accumulated provision for depreciation	4,170	4,152
Construction work in progress	130	148
Total net property, plant and equipment	4,300	4,300
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in affiliated companies	0	0
Other	11	11
Total other property and investments	11	11
ASSETS HELD FOR SALE		122
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	105	131
Customer intangibles	0	0
Goodwill	0	0
Property taxes	11	15
Unamortized sale and leaseback costs	0	0
Derivatives	0	0
Other	223	228
Total deferred charges and other assets	339	374
Total assets	5,531	5,840
CURRENT LIABILITIES:
Currently payable long-term debt	120	367
Short-term borrowings	5	4
Accounts payable-
Affiliated companies	19	400
Other	112	196
Accrued taxes	68	23
Derivatives	0	0
Other	62	63
Total current liabilities	669	1,265
CAPITALIZATION:
Total equity	2,343	2,283
Long-term debt and other long-term obligations	2,094	1,860
Total capitalization	4,437	4,143
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	0	0
Accumulated deferred income taxes	0	0
Asset retirement obligations	188	187
Retirement benefits	167	163
Derivatives	0	0
Other	70	82
Total noncurrent liabilities	425	432
Total liabilities and capitalization	5,531	5,840
FGCO | Affiliates
CURRENT LIABILITIES:
Short-term borrowings	283	212
Nuclear Generation Corp
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	0	0
Affiliated companies	180	227
Other Receivables	73	17
Notes receivable from affiliated companies	230	683
Materials and supplies, at average cost	216	213
Derivatives	0	0
Collateral	0	0
Prepayments and other	0	7
Total current assets	699	1,147
PROPERTY, PLANT AND EQUIPMENT:
In service	6,925	6,645
Less - Accumulated provision for depreciation	3,038	2,962
Property, plant and equipment in service net of accumulated provision for depreciation	3,887	3,683
Construction work in progress	1,200	1,137
Total net property, plant and equipment	5,087	4,820
INVESTMENTS:
Nuclear plant decommissioning trusts	1,323	1,276
Investment in affiliated companies	0	0
Other	0	0
Total other property and investments	1,323	1,276
ASSETS HELD FOR SALE		0
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	0	0
Customer intangibles	0	0
Goodwill	0	0
Property taxes	19	26
Unamortized sale and leaseback costs	0	0
Derivatives	0	0
Other	9	18
Total deferred charges and other assets	28	44
Total assets	7,137	7,287
CURRENT LIABILITIES:
Currently payable long-term debt	366	547
Short-term borrowings	0	0
Accounts payable-
Affiliated companies	240	362
Other	0	0
Accrued taxes	38	23
Derivatives	0	0
Other	21	18
Total current liabilities	665	1,101
CAPITALIZATION:
Total equity	3,548	3,493
Long-term debt and other long-term obligations	931	742
Total capitalization	4,479	4,235
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	0	0
Accumulated deferred income taxes	763	736
Asset retirement obligations	841	828
Retirement benefits	0	0
Derivatives	0	0
Other	389	387
Total noncurrent liabilities	1,993	1,951
Total liabilities and capitalization	7,137	7,287
Nuclear Generation Corp | Affiliates
CURRENT LIABILITIES:
Short-term borrowings	0	151
Eliminations
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	0	0
Affiliated companies	(274)	(916)
Other Receivables	0	0
Notes receivable from affiliated companies	(921)	(909)
Materials and supplies, at average cost	0	0
Derivatives	0	0
Collateral	0	0
Prepayments and other	0	0
Total current assets	(1,195)	(1,825)
PROPERTY, PLANT AND EQUIPMENT:
In service	(383)	(382)
Less - Accumulated provision for depreciation	(189)	(188)
Property, plant and equipment in service net of accumulated provision for depreciation	(194)	(194)
Construction work in progress	0	0
Total net property, plant and equipment	(194)	(194)
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in affiliated companies	(5,891)	(5,801)
Other	0	0
Total other property and investments	(5,891)	(5,801)
ASSETS HELD FOR SALE		0
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	(105)	(131)
Customer intangibles	0	0
Goodwill	0	0
Property taxes	0	0
Unamortized sale and leaseback costs	197	168
Derivatives	0	0
Other	(154)	(155)
Total deferred charges and other assets	(62)	(118)
Total assets	(7,342)	(7,938)
CURRENT LIABILITIES:
Currently payable long-term debt	(22)	(23)
Short-term borrowings	0	0
Accounts payable-
Affiliated companies	(305)	(738)
Other	0	0
Accrued taxes	(12)	(184)
Derivatives	0	0
Other	80	46
Total current liabilities	(1,178)	(1,808)
CAPITALIZATION:
Total equity	(5,865)	(5,776)
Long-term debt and other long-term obligations	(1,186)	(1,184)
Total capitalization	(7,051)	(6,960)
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	850	858
Accumulated deferred income taxes	36	(27)
Asset retirement obligations	0	0
Retirement benefits	0	0
Derivatives	0	0
Other	1	(1)
Total noncurrent liabilities	887	830
Total liabilities and capitalization	(7,342)	(7,938)
Eliminations | Affiliates
CURRENT LIABILITIES:
Short-term borrowings	(919)	(909)
FES
CURRENT ASSETS:
Cash and cash equivalents	2	2	3	3
Receivables-
Customers	583	539
Affiliated companies	369	1,036
Other Receivables	151	81
Notes receivable from affiliated companies	215	0
Materials and supplies, at average cost	427	448
Derivatives	244	165
Collateral	544	136
Prepayments and other	179	109
Total current assets	2,714	2,516
PROPERTY, PLANT AND EQUIPMENT:
In service	12,796	12,472
Less - Accumulated provision for depreciation	4,857	4,755
Property, plant and equipment in service net of accumulated provision for depreciation	7,939	7,717
Construction work in progress	1,356	1,308
Total net property, plant and equipment	9,295	9,025
INVESTMENTS:
Nuclear plant decommissioning trusts	1,323	1,276
Investment in affiliated companies	0	0
Other	11	11
Total other property and investments	1,334	1,287
ASSETS HELD FOR SALE	0	122
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	0	0
Customer intangibles	91	95
Goodwill	23	23
Property taxes	30	41
Unamortized sale and leaseback costs	197	168
Derivatives	65	53
Other	150	172
Total deferred charges and other assets	556	552
Total assets	13,899	13,502
CURRENT LIABILITIES:
Currently payable long-term debt	465	892
Short-term borrowings	555	4
Accounts payable-
Affiliated companies	327	765
Other	295	290
Accrued taxes	97	66
Derivatives	159	110
Other	214	197
Total current liabilities	2,112	2,755
CAPITALIZATION:
Total equity	5,833	5,312
Long-term debt and other long-term obligations	2,551	2,130
Total capitalization	8,384	7,442
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	850	858
Accumulated deferred income taxes	810	741
Asset retirement obligations	1,029	1,015
Retirement benefits	189	185
Derivatives	36	14
Other	489	492
Total noncurrent liabilities	3,403	3,305
Total liabilities and capitalization	13,899	13,502
FES | Affiliates
CURRENT LIABILITIES:
Short-term borrowings	$ 0	$ 431