Supplemental Guarantor Information (Details 1) (USD $)	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
CURRENT ASSETS:
Cash and cash equivalents	$ 202,000,000	$ 1,019,000,000	$ 874,000,000	$ 545,000,000
Receivables-
Customers	1,525,000,000	1,392,000,000
Other	269,000,000	176,000,000
Materials and supplies, at average cost	811,000,000	638,000,000
Derivatives	235,000,000	182,000,000
Prepayments and other	122,000,000	92,000,000
Total current assets	3,355,000,000	3,698,000,000
PROPERTY, PLANT AND EQUIPMENT:
In service	40,122,000,000	30,276,000,000
Less - Accumulated provision for depreciation	11,839,000,000	11,283,000,000
Property, plant and equipment in service net of accumulated provision for depreciation	28,283,000,000	18,993,000,000
Construction work in progress	2,054,000,000	1,517,000,000
Total net property, plant and equipment	30,337,000,000	20,510,000,000
INVESTMENTS:
Nuclear plant decommissioning trusts	2,112,000,000	1,973,000,000
Other	1,008,000,000	553,000,000
Total other property and investments	3,522,000,000	3,002,000,000
DEFERRED CHARGES AND OTHER ASSETS:
Customer intangibles	803,000,000
Goodwill	6,441,000,000	5,575,000,000	5,575,000,000
Other	1,641,000,000	916,000,000
Total deferred charges and other assets	10,112,000,000	8,321,000,000
Total assets	47,326,000,000	35,531,000,000	35,054,000,000
CURRENT LIABILITIES:
Currently payable long-term debt	1,621,000,000	1,486,000,000
Short-term borrowings-
Affiliated companies	0	700,000,000
Accounts payable-
Accrued taxes	558,000,000	332,000,000
Derivatives	218,000,000	266,000,000
Other	900,000,000	733,000,000
Total current liabilities	4,855,000,000	4,704,000,000
CAPITALIZATION:
Total equity	13,280,000,000	8,984,000,000
Long-term debt and other long-term obligations	15,716,000,000	12,579,000,000
Total capitalization	29,015,000,000	21,531,000,000
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback	925,000,000	959,000,000
Accumulated deferred income taxes	5,670,000,000	3,160,000,000
Asset retirement obligations	1,497,000,000	1,407,000,000
Retirement benefits	2,823,000,000	1,868,000,000
Other	2,072,000,000	1,436,000,000
Total noncurrent liabilities	13,456,000,000	9,296,000,000
Total liabilities and capitalization	47,326,000,000	35,531,000,000
FES Corp
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	424,000,000	366,000,000
Affiliated companies	476,000,000	333,000,000
Other	28,000,000	21,000,000
Notes receivable from affiliated companies	155,000,000	34,000,000
Materials and supplies, at average cost	60,000,000	41,000,000
Derivatives	219,000,000	181,000,000
Prepayments and other	11,000,000	48,000,000
Total current assets	1,373,000,000	1,024,000,000
PROPERTY, PLANT AND EQUIPMENT:
In service	84,000,000	99,000,000
Less - Accumulated provision for depreciation	28,000,000	18,000,000
Property, plant and equipment in service net of accumulated provision for depreciation	56,000,000	81,000,000
Construction work in progress	29,000,000	9,000,000
Total net property, plant and equipment	85,000,000	90,000,000
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in associated companies	5,716,000,000	4,773,000,000
Other	0	0
Total other property and investments	5,716,000,000	4,773,000,000
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	10,000,000	42,000,000
Customer intangibles	123,000,000	134,000,000
Goodwill	24,000,000	24,000,000
Property taxes	0	0
Unamortized sale and leaseback costs	0	0
Derivatives	118,000,000	98,000,000
Other	50,000,000	22,000,000
Total deferred charges and other assets	325,000,000	320,000,000
Total assets	7,499,000,000	6,207,000,000
CURRENT LIABILITIES:
Currently payable long-term debt	1,000,000	101,000,000
Accounts payable-
Affiliated companies	777,000,000	351,000,000
Other	99,000,000	139,000,000
Derivatives	189,000,000	266,000,000
Other	62,000,000	52,000,000
Total current liabilities	2,277,000,000	912,000,000
CAPITALIZATION:
Total equity	3,593,000,000	3,619,000,000
Long-term debt and other long-term obligations	1,483,000,000	1,519,000,000
Total capitalization	5,076,000,000	5,138,000,000
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback	0	0
Accumulated deferred income taxes	12,000,000	0
Asset retirement obligations	0	0
Retirement benefits	56,000,000	48,000,000
Lease market valuation liability	0	0
Other	78,000,000	109,000,000
Total noncurrent liabilities	146,000,000	157,000,000
Total liabilities and capitalization	7,499,000,000	6,207,000,000
FES Corp | Affiliates
Short-term borrowings-
Affiliated companies	1,065,000,000	0
Accounts payable-
Accrued taxes	84,000,000	3,000,000
FGCO
CURRENT ASSETS:
Cash and cash equivalents	7,000,000	9,000,000	0	0
Receivables-
Customers	0	0
Affiliated companies	643,000,000	357,000,000
Other	20,000,000	56,000,000
Notes receivable from affiliated companies	1,346,000,000	189,000,000
Materials and supplies, at average cost	232,000,000	276,000,000
Derivatives	0	0
Prepayments and other	26,000,000	11,000,000
Total current assets	2,274,000,000	898,000,000
PROPERTY, PLANT AND EQUIPMENT:
In service	5,573,000,000	6,214,000,000
Less - Accumulated provision for depreciation	1,813,000,000	2,022,000,000
Property, plant and equipment in service net of accumulated provision for depreciation	3,760,000,000	4,192,000,000
Construction work in progress	195,000,000	520,000,000
Total net property, plant and equipment	3,955,000,000	4,712,000,000
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in associated companies	0	0
Other	7,000,000	12,000,000
Total other property and investments	7,000,000	12,000,000
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	307,000,000	407,000,000
Customer intangibles	0	0
Goodwill	0	0
Property taxes	20,000,000	16,000,000
Unamortized sale and leaseback costs	5,000,000	10,000,000
Derivatives	0	0
Other	99,000,000	70,000,000
Total deferred charges and other assets	431,000,000	503,000,000
Total assets	6,667,000,000	6,125,000,000
CURRENT LIABILITIES:
Currently payable long-term debt	411,000,000	419,000,000
Accounts payable-
Affiliated companies	228,000,000	213,000,000
Other	121,000,000	102,000,000
Derivatives	0	0
Other	141,000,000	148,000,000
Total current liabilities	1,032,000,000	930,000,000
CAPITALIZATION:
Total equity	3,097,000,000	2,495,000,000
Long-term debt and other long-term obligations	1,905,000,000	2,119,000,000
Total capitalization	5,002,000,000	4,614,000,000
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback	0	0
Accumulated deferred income taxes	0	0
Asset retirement obligations	28,000,000	27,000,000
Retirement benefits	300,000,000	237,000,000
Lease market valuation liability	171,000,000	217,000,000
Other	134,000,000	100,000,000
Total noncurrent liabilities	633,000,000	581,000,000
Total liabilities and capitalization	6,667,000,000	6,125,000,000
FGCO | Affiliates
Short-term borrowings-
Affiliated companies	89,000,000	12,000,000
Accounts payable-
Accrued taxes	42,000,000	36,000,000
Nuclear Generation Corp
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	0	0
Affiliated companies	262,000,000	126,000,000
Other	13,000,000	13,000,000
Notes receivable from affiliated companies	69,000,000	174,000,000
Materials and supplies, at average cost	200,000,000	228,000,000
Derivatives	0	0
Prepayments and other	1,000,000	1,000,000
Total current assets	545,000,000	542,000,000
PROPERTY, PLANT AND EQUIPMENT:
In service	5,711,000,000	5,499,000,000
Less - Accumulated provision for depreciation	2,449,000,000	2,173,000,000
Property, plant and equipment in service net of accumulated provision for depreciation	3,262,000,000	3,326,000,000
Construction work in progress	790,000,000	534,000,000
Total net property, plant and equipment	4,052,000,000	3,860,000,000
INVESTMENTS:
Nuclear plant decommissioning trusts	1,223,000,000	1,146,000,000
Investment in associated companies	0	0
Other	0	0
Total other property and investments	1,223,000,000	1,146,000,000
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	0	0
Customer intangibles	0	0
Goodwill	0	0
Property taxes	23,000,000	25,000,000
Unamortized sale and leaseback costs	0	0
Derivatives	0	0
Other	3,000,000	14,000,000
Total deferred charges and other assets	26,000,000	39,000,000
Total assets	5,846,000,000	5,587,000,000
CURRENT LIABILITIES:
Currently payable long-term debt	513,000,000	632,000,000
Accounts payable-
Affiliated companies	211,000,000	250,000,000
Other	0	0
Derivatives	0	0
Other	16,000,000	15,000,000
Total current liabilities	882,000,000	928,000,000
CAPITALIZATION:
Total equity	2,587,000,000	2,265,000,000
Long-term debt and other long-term obligations	641,000,000	793,000,000
Total capitalization	3,228,000,000	3,058,000,000
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback	0	0
Accumulated deferred income taxes	510,000,000	449,000,000
Asset retirement obligations	876,000,000	865,000,000
Retirement benefits	0	0
Lease market valuation liability	0	0
Other	350,000,000	287,000,000
Total noncurrent liabilities	1,736,000,000	1,601,000,000
Total liabilities and capitalization	5,846,000,000	5,587,000,000
Nuclear Generation Corp | Affiliates
Short-term borrowings-
Affiliated companies	32,000,000	0
Accounts payable-
Accrued taxes	110,000,000	31,000,000
Eliminations
CURRENT ASSETS:
Cash and cash equivalents	0	0	0	0
Receivables-
Customers	0	0
Affiliated companies	(781,000,000)	(338,000,000)
Other	0	0
Notes receivable from affiliated companies	(1,187,000,000)	0
Materials and supplies, at average cost	0	0
Derivatives	0	0
Prepayments and other	0	0
Total current assets	(1,968,000,000)	(338,000,000)
PROPERTY, PLANT AND EQUIPMENT:
In service	(385,000,000)	(385,000,000)
Less - Accumulated provision for depreciation	(180,000,000)	(175,000,000)
Property, plant and equipment in service net of accumulated provision for depreciation	(205,000,000)	(210,000,000)
Construction work in progress	0	0
Total net property, plant and equipment	(205,000,000)	(210,000,000)
INVESTMENTS:
Nuclear plant decommissioning trusts	0	0
Investment in associated companies	(5,716,000,000)	(4,773,000,000)
Other	0	0
Total other property and investments	(5,716,000,000)	(4,773,000,000)
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	(317,000,000)	(449,000,000)
Customer intangibles	0	0
Goodwill	0	0
Property taxes	0	0
Unamortized sale and leaseback costs	75,000,000	63,000,000
Derivatives	0	0
Other	(62,000,000)	(57,000,000)
Total deferred charges and other assets	(304,000,000)	(443,000,000)
Total assets	(8,193,000,000)	(5,764,000,000)
CURRENT LIABILITIES:
Currently payable long-term debt	(20,000,000)	(20,000,000)
Accounts payable-
Affiliated companies	(780,000,000)	(348,000,000)
Other	0	0
Derivatives	0	0
Other	42,000,000	37,000,000
Total current liabilities	(1,953,000,000)	(331,000,000)
CAPITALIZATION:
Total equity	(5,700,000,000)	(4,760,000,000)
Long-term debt and other long-term obligations	(1,230,000,000)	(1,250,000,000)
Total capitalization	(6,930,000,000)	(6,010,000,000)
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback	925,000,000	959,000,000
Accumulated deferred income taxes	(236,000,000)	(382,000,000)
Asset retirement obligations	0	0
Retirement benefits	0	0
Lease market valuation liability	0	0
Other	1,000,000	0
Total noncurrent liabilities	690,000,000	577,000,000
Total liabilities and capitalization	(8,193,000,000)	(5,764,000,000)
Eliminations | Affiliates
Short-term borrowings-
Affiliated companies	(1,186,000,000)	0
Accounts payable-
Accrued taxes	(9,000,000)	0
FES
CURRENT ASSETS:
Cash and cash equivalents	7,000,000	9,000,000	0	0
Receivables-
Customers	424,000,000	366,000,000
Affiliated companies	600,000,000	478,000,000
Other	61,000,000	90,000,000
Notes receivable from affiliated companies	383,000,000	397,000,000
Materials and supplies, at average cost	492,000,000	545,000,000
Derivatives	219,000,000	181,000,000
Prepayments and other	38,000,000	60,000,000
Total current assets	2,224,000,000	2,126,000,000
PROPERTY, PLANT AND EQUIPMENT:
In service	10,983,000,000	11,427,000,000
Less - Accumulated provision for depreciation	4,110,000,000	4,038,000,000
Property, plant and equipment in service net of accumulated provision for depreciation	6,873,000,000	7,389,000,000
Construction work in progress	1,014,000,000	1,063,000,000
Total net property, plant and equipment	7,887,000,000	8,452,000,000
INVESTMENTS:
Nuclear plant decommissioning trusts	1,223,000,000	1,146,000,000
Investment in associated companies	0	0
Other	7,000,000	12,000,000
Total other property and investments	1,230,000,000	1,158,000,000
DEFERRED CHARGES AND OTHER ASSETS:
Accumulated deferred income tax benefits	0	0
Customer intangibles	123,000,000	134,000,000
Goodwill	24,000,000	24,000,000
Property taxes	43,000,000	41,000,000
Unamortized sale and leaseback costs	80,000,000	73,000,000
Derivatives	118,000,000	98,000,000
Other	90,000,000	49,000,000
Total deferred charges and other assets	478,000,000	419,000,000
Total assets	11,819,000,000	12,155,000,000
CURRENT LIABILITIES:
Currently payable long-term debt	905,000,000	1,132,000,000
Accounts payable-
Affiliated companies	436,000,000	466,000,000
Other	220,000,000	241,000,000
Accrued taxes	227,000,000	70,000,000
Derivatives	189,000,000	266,000,000
Other	261,000,000	252,000,000
Total current liabilities	2,238,000,000	2,439,000,000
CAPITALIZATION:
Total equity	3,577,000,000	3,619,000,000
Long-term debt and other long-term obligations	2,799,000,000	3,181,000,000
Total capitalization	6,376,000,000	6,800,000,000
NONCURRENT LIABILITIES:
Deferred gain on sale and leaseback	925,000,000	959,000,000
Accumulated deferred income taxes	286,000,000	67,000,000
Asset retirement obligations	904,000,000	892,000,000
Retirement benefits	356,000,000	285,000,000
Lease market valuation liability	171,000,000	217,000,000
Other	563,000,000	496,000,000
Total noncurrent liabilities	3,205,000,000	2,916,000,000
Total liabilities and capitalization	11,819,000,000	12,155,000,000
FES | Affiliates
Short-term borrowings-
Affiliated companies	0	12,000,000
Accounts payable-
Accrued taxes	$ 227,000,000	$ 70,000,000