Supplemental Guarantor Information (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CURRENT ASSETS:
Cash and cash equivalents	$ 218	$ 172	$ 202	$ 1,019
Receivables-
Customers	1,720	1,614
Other Receivables	198	315
Materials and supplies, at average cost	752	861
Derivatives	166	160
Prepayments and other	241	208
Total current assets	3,887	3,768
PROPERTY, PLANT AND EQUIPMENT:
In service	44,228	43,210
Less - Accumulated provision for depreciation	13,280	12,467
Property, plant and equipment in service net of accumulated provision for depreciation	30,948	30,743
Construction work in progress	2,304	2,293
Total net property, plant and equipment	33,252	33,036
INVESTMENTS:
Nuclear plant decommissioning trusts	2,201	2,204
Other	870	936
Total other property and investments	3,104	3,194
ASSETS HELD FOR SALE (Note 20)	235	0
DEFERRED CHARGES AND OTHER ASSETS:
Customer intangibles	588
Goodwill	6,418	6,447	6,441
Other	1,674	1,719
Total deferred charges and other assets	9,946	10,496
Total assets	50,424	50,494	47,410
CURRENT LIABILITIES:
Currently payable long-term debt	1,415	1,999
Short-term borrowings	3,404	1,969
Accounts payable-
Accrued taxes	485	543
Derivatives	111	126
Other	621	1,038
Total current liabilities	7,637	7,605
CAPITALIZATION:
Total equity	12,692	13,084
Long-term debt and other long-term obligations	15,831	15,179
Total capitalization	28,526	28,272
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	858	892
Accumulated deferred income taxes	6,968	6,616
Asset retirement obligations	1,678	1,599
Retirement benefits	2,689	3,080
Other	1,778	1,924
Total noncurrent liabilities	14,261	14,617
Total liabilities and capitalization	50,424	50,494
FES
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	539	483
Affiliated companies	938	232
Other Receivables	52	56
Notes receivable from affiliated companies	203	366
Materials and supplies, at average cost	76	66
Derivatives	165	158
Prepayments and other	81	38
Total current assets	2,054	1,399
PROPERTY, PLANT AND EQUIPMENT:
In service	104	91
Less - Accumulated provision for depreciation	28	32
Property, plant and equipment in service net of accumulated provision for depreciation	76	59
Construction work in progress	23	34
Total net property, plant and equipment	99	93
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in affiliated companies	5,801	4,972
Other	0	0
Total other property and investments	5,801	4,972
ASSETS HELD FOR SALE (Note 20)	0	0
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	0	0
Customer intangibles	95	110
Goodwill	23	24
Property taxes	0	0
Unamortized sale and leaseback costs	0	0
Derivatives	53	99
Other	188	160
Total deferred charges and other assets	359	393
Total assets	8,313	6,857
CURRENT LIABILITIES:
Currently payable long-term debt	1	1
Short-term borrowings	0	0
Accounts payable-
Affiliated companies	741	748
Other	94	63
Accrued taxes	204	126
Derivatives	110	124
Other	70	71
Total current liabilities	2,197	1,491
CAPITALIZATION:
Total equity	5,312	3,763
Long-term debt and other long-term obligations	712	1,482
Total capitalization	6,024	5,245
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	0	0
Accumulated deferred income taxes	32	28
Asset retirement obligations	0	0
Retirement benefits	22	26
Derivatives	14	37
Other	24	30
Total noncurrent liabilities	92	121
Total liabilities and capitalization	8,313	6,857
FES | Affiliates
CURRENT LIABILITIES:
Other Short-term Borrowings	977	358
FGCO
CURRENT ASSETS:
Cash and cash equivalents	2	3	7	9
Receivables-
Customers	0	0
Affiliated companies	787	417
Other Receivables	12	19
Notes receivable from affiliated companies	23	7
Materials and supplies, at average cost	159	231
Derivatives	0	0
Prepayments and other	50	39
Total current assets	1,033	716
PROPERTY, PLANT AND EQUIPMENT:
In service	6,105	5,899
Less - Accumulated provision for depreciation	1,953	1,915
Property, plant and equipment in service net of accumulated provision for depreciation	4,152	3,984
Construction work in progress	148	230
Total net property, plant and equipment	4,300	4,214
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in affiliated companies	0	0
Other	11	12
Total other property and investments	11	12
ASSETS HELD FOR SALE (Note 20)	122	0
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	131	313
Customer intangibles	0	0
Goodwill	0	0
Property taxes	15	14
Unamortized sale and leaseback costs	0	0
Derivatives	0	0
Other	228	194
Total deferred charges and other assets	374	521
Total assets	5,840	5,463
CURRENT LIABILITIES:
Currently payable long-term debt	367	586
Short-term borrowings	4	4
Accounts payable-
Affiliated companies	400	143
Other	196	96
Accrued taxes	23	25
Derivatives	0	0
Other	63	148
Total current liabilities	1,265	1,348
CAPITALIZATION:
Total equity	2,283	1,787
Long-term debt and other long-term obligations	1,860	2,009
Total capitalization	4,143	3,796
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	0	0
Accumulated deferred income taxes	0	0
Asset retirement obligations	187	29
Retirement benefits	163	215
Derivatives	0	0
Other	82	75
Total noncurrent liabilities	432	319
Total liabilities and capitalization	5,840	5,463
FGCO | Affiliates
CURRENT LIABILITIES:
Other Short-term Borrowings	212	346
Nuclear Generation Corp
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	0	0
Affiliated companies	227	478
Other Receivables	17	16
Notes receivable from affiliated companies	683	607
Materials and supplies, at average cost	213	208
Derivatives	0	0
Prepayments and other	7	10
Total current assets	1,147	1,319
PROPERTY, PLANT AND EQUIPMENT:
In service	6,645	6,391
Less - Accumulated provision for depreciation	2,962	2,646
Property, plant and equipment in service net of accumulated provision for depreciation	3,683	3,745
Construction work in progress	1,137	877
Total net property, plant and equipment	4,820	4,622
INVESTMENTS:
Nuclear plant decommissioning trusts	1,276	1,283
Investment in affiliated companies	0	0
Other	0	0
Total other property and investments	1,276	1,283
ASSETS HELD FOR SALE (Note 20)	0	0
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	0	0
Customer intangibles	0	0
Goodwill	0	0
Property taxes	26	22
Unamortized sale and leaseback costs	0	0
Derivatives	0	0
Other	18	5
Total deferred charges and other assets	44	27
Total assets	7,287	7,251
CURRENT LIABILITIES:
Currently payable long-term debt	547	537
Short-term borrowings	0	0
Accounts payable-
Affiliated companies	362	583
Other	0	0
Accrued taxes	23	20
Derivatives	0	0
Other	18	15
Total current liabilities	1,101	1,155
CAPITALIZATION:
Total equity	3,493	3,165
Long-term debt and other long-term obligations	742	834
Total capitalization	4,235	3,999
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	0	0
Accumulated deferred income taxes	736	714
Asset retirement obligations	828	936
Retirement benefits	0	0
Derivatives	0	0
Other	387	447
Total noncurrent liabilities	1,951	2,097
Total liabilities and capitalization	7,287	7,251
Nuclear Generation Corp | Affiliates
CURRENT LIABILITIES:
Other Short-term Borrowings	151	0
Eliminations
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	0	0
Affiliated companies	(916)	(748)
Other Receivables	0	0
Notes receivable from affiliated companies	(909)	(704)
Materials and supplies, at average cost	0	0
Derivatives	0	0
Prepayments and other	0	0
Total current assets	(1,825)	(1,452)
PROPERTY, PLANT AND EQUIPMENT:
In service	(382)	(384)
Less - Accumulated provision for depreciation	(188)	(185)
Property, plant and equipment in service net of accumulated provision for depreciation	(194)	(199)
Construction work in progress	0	0
Total net property, plant and equipment	(194)	(199)
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in affiliated companies	(5,801)	(4,972)
Other	0	0
Total other property and investments	(5,801)	(4,972)
ASSETS HELD FOR SALE (Note 20)	0	0
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	(131)	(313)
Customer intangibles	0	0
Goodwill	0	0
Property taxes	0	0
Unamortized sale and leaseback costs	168	119
Derivatives	0	0
Other	(155)	(106)
Total deferred charges and other assets	(118)	(300)
Total assets	(7,938)	(6,923)
CURRENT LIABILITIES:
Currently payable long-term debt	(23)	(22)
Short-term borrowings	0	0
Accounts payable-
Affiliated companies	(738)	(748)
Other	0	0
Accrued taxes	(184)	0
Derivatives	0	0
Other	46	46
Total current liabilities	(1,808)	(1,428)
CAPITALIZATION:
Total equity	(5,776)	(4,952)
Long-term debt and other long-term obligations	(1,184)	(1,207)
Total capitalization	(6,960)	(6,159)
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	858	892
Accumulated deferred income taxes	(27)	(227)
Asset retirement obligations	0	0
Retirement benefits	0	0
Derivatives	0	0
Other	(1)	(1)
Total noncurrent liabilities	830	664
Total liabilities and capitalization	(7,938)	(6,923)
Eliminations | Affiliates
CURRENT LIABILITIES:
Other Short-term Borrowings	(909)	(704)
FES
CURRENT ASSETS:
Cash and cash equivalents	2	3	7	9
Receivables-
Customers	539	483
Affiliated companies	1,036	379
Other Receivables	81	91
Notes receivable from affiliated companies	0	276
Materials and supplies, at average cost	448	505
Derivatives	165	158
Prepayments and other	138	87
Total current assets	2,409	1,982
PROPERTY, PLANT AND EQUIPMENT:
In service	12,472	11,997
Less - Accumulated provision for depreciation	4,755	4,408
Property, plant and equipment in service net of accumulated provision for depreciation	7,717	7,589
Construction work in progress	1,308	1,141
Total net property, plant and equipment	9,025	8,730
INVESTMENTS:
Nuclear plant decommissioning trusts	1,276	1,283
Investment in affiliated companies	0	0
Other	11	12
Total other property and investments	1,287	1,295
ASSETS HELD FOR SALE (Note 20)	122	0
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	0	0
Customer intangibles	95	110
Goodwill	23	24
Property taxes	41	36
Unamortized sale and leaseback costs	168	119
Derivatives	53	99
Other	279	253
Total deferred charges and other assets	659	641
Total assets	13,502	12,648
CURRENT LIABILITIES:
Currently payable long-term debt	892	1,102
Short-term borrowings	4	4
Accounts payable-
Affiliated companies	765	726
Other	290	159
Accrued taxes	66	171
Derivatives	110	124
Other	197	280
Total current liabilities	2,755	2,566
CAPITALIZATION:
Total equity	5,312	3,763
Long-term debt and other long-term obligations	2,130	3,118
Total capitalization	7,442	6,881
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback transaction	858	892
Accumulated deferred income taxes	741	515
Asset retirement obligations	1,015	965
Retirement benefits	185	241
Derivatives	14	37
Other	492	551
Total noncurrent liabilities	3,305	3,201
Total liabilities and capitalization	13,502	12,648
FES | Affiliates
CURRENT LIABILITIES:
Other Short-term Borrowings	$ 431	$ 0