Supplemental Guarantor Information (Details) (USD $)	3 Months Ended				6 Months Ended
	Jun. 30, 2011		Jun. 30, 2010		Jun. 30, 2011		Jun. 30, 2010
Consolidating Statements of Income
Revenues	$ 4,060,000,000	[1]	$ 3,139,000,000	[1]	$ 7,636,000,000	[1]	$ 6,438,000,000	[1]
EXPENSES:
Fuel	635,000,000		350,000,000		1,088,000,000		684,000,000
Purchased power	1,220,000,000		1,063,000,000		2,406,000,000		2,301,000,000
Other operating expenses	1,105,000,000		673,000,000		2,138,000,000		1,374,000,000
Provision for depreciation	282,000,000		190,000,000		502,000,000		383,000,000
General taxes	242,000,000		176,000,000		479,000,000		381,000,000
Total expenses	3,574,000,000		2,613,000,000		6,835,000,000		5,496,000,000
OPERATING INCOME	486,000,000		526,000,000		801,000,000		942,000,000
OTHER INCOME (EXPENSE):
Investment income	31,000,000		31,000,000		52,000,000		47,000,000
Interest expense	(265,000,000)		(207,000,000)		(496,000,000)		(420,000,000)
Capitalized interest	20,000,000		40,000,000		38,000,000		81,000,000
Total other expense	(214,000,000)		(136,000,000)		(406,000,000)		(292,000,000)
INCOME (LOSS) BEFORE INCOME TAXES	272,000,000		390,000,000		395,000,000		650,000,000
INCOME TAXES	101,000,000		134,000,000		179,000,000		245,000,000
NET INCOME	171,000,000		256,000,000		216,000,000		405,000,000
FES Corp
Consolidating Statements of Income
Revenues	1,275,000,000		1,307,000,000		2,642,000,000		2,674,000,000
EXPENSES:
Fuel	6,000,000		7,000,000		7,000,000		12,000,000
Other operating expenses	159,000,000		81,000,000		321,000,000		134,000,000
Provision for depreciation	1,000,000		1,000,000		2,000,000		2,000,000
General taxes	16,000,000		6,000,000		27,000,000		11,000,000
Total expenses	1,416,000,000		1,318,000,000		3,073,000,000		2,800,000,000
OPERATING INCOME	(141,000,000)		(11,000,000)		(431,000,000)		(126,000,000)
OTHER INCOME (EXPENSE):
Investment income			2,000,000		1,000,000		4,000,000
Miscellaneous income, including net income from equity investees	123,000,000		151,000,000		356,000,000		317,000,000
Interest expense	(24,000,000)		(24,000,000)		(48,000,000)		(48,000,000)
Total other expense	99,000,000		129,000,000		308,000,000		273,000,000
INCOME (LOSS) BEFORE INCOME TAXES	(42,000,000)		118,000,000		(123,000,000)		147,000,000
INCOME TAXES	(62,000,000)		(16,000,000)		(179,000,000)		(67,000,000)
NET INCOME	20,000,000		134,000,000		56,000,000		214,000,000
Affiliates | FES Corp
EXPENSES:
Purchased power	902,000,000		913,000,000		2,087,000,000		1,881,000,000
OTHER INCOME (EXPENSE):
Interest expense					(1,000,000)
Non-Affiliates | FES Corp
EXPENSES:
Purchased power	332,000,000		310,000,000		629,000,000		760,000,000
FGCO
Consolidating Statements of Income
Revenues	535,000,000		581,000,000		1,278,000,000		1,149,000,000
EXPENSES:
Fuel	266,000,000		302,000,000		560,000,000		582,000,000
Other operating expenses	115,000,000		94,000,000		233,000,000		194,000,000
Provision for depreciation	32,000,000		27,000,000		63,000,000		54,000,000
General taxes	8,000,000		9,000,000		19,000,000		24,000,000
Impairment of long-lived assets	7,000,000				20,000,000		2,000,000
Total expenses	434,000,000		440,000,000		903,000,000		868,000,000
OPERATING INCOME	101,000,000		141,000,000		375,000,000		281,000,000
OTHER INCOME (EXPENSE):
Investment income	1,000,000				1,000,000
Miscellaneous income, including net income from equity investees	1,000,000		1,000,000		2,000,000		1,000,000
Interest expense	(28,000,000)		(28,000,000)		(56,000,000)		(54,000,000)
Capitalized interest	5,000,000		20,000,000		10,000,000		36,000,000
Total other expense	(22,000,000)		(9,000,000)		(44,000,000)		(21,000,000)
INCOME (LOSS) BEFORE INCOME TAXES	79,000,000		132,000,000		331,000,000		260,000,000
INCOME TAXES	25,000,000		48,000,000		119,000,000		97,000,000
NET INCOME	54,000,000		84,000,000		212,000,000		163,000,000
Affiliates | FGCO
EXPENSES:
Purchased power	9,000,000		8,000,000		11,000,000		12,000,000
OTHER INCOME (EXPENSE):
Interest expense	(1,000,000)		(2,000,000)		(1,000,000)		(4,000,000)
Non-Affiliates | FGCO
EXPENSES:
Purchased power	(3,000,000)				(3,000,000)
Nuclear Generation Corp
Consolidating Statements of Income
Revenues	393,000,000		339,000,000		862,000,000		765,000,000
EXPENSES:
Fuel	44,000,000		34,000,000		92,000,000		77,000,000
Other operating expenses	143,000,000		117,000,000		331,000,000		256,000,000
Provision for depreciation	36,000,000		36,000,000		74,000,000		73,000,000
General taxes	6,000,000		7,000,000		14,000,000		14,000,000
Total expenses	294,000,000		243,000,000		645,000,000		531,000,000
OPERATING INCOME	99,000,000		96,000,000		217,000,000		234,000,000
OTHER INCOME (EXPENSE):
Investment income	15,000,000		11,000,000		20,000,000		10,000,000
Interest expense	(16,000,000)		(15,000,000)		(33,000,000)		(31,000,000)
Capitalized interest	5,000,000		4,000,000		10,000,000		8,000,000
Total other expense	3,000,000				(4,000,000)		(14,000,000)
INCOME (LOSS) BEFORE INCOME TAXES	102,000,000		96,000,000		213,000,000		220,000,000
INCOME TAXES	38,000,000		34,000,000		80,000,000		78,000,000
NET INCOME	64,000,000		62,000,000		133,000,000		142,000,000
Affiliates | Nuclear Generation Corp
EXPENSES:
Purchased power	65,000,000		49,000,000		134,000,000		111,000,000
OTHER INCOME (EXPENSE):
Interest expense	(1,000,000)				(1,000,000)		(1,000,000)
Eliminations
Consolidating Statements of Income
Revenues	(911,000,000)		(901,000,000)		(2,098,000,000)		(1,874,000,000)
EXPENSES:
Other operating expenses	12,000,000		12,000,000		25,000,000		24,000,000
Provision for depreciation	(1,000,000)		(1,000,000)		(3,000,000)		(3,000,000)
Total expenses	(900,000,000)		(890,000,000)		(2,076,000,000)		(1,853,000,000)
OPERATING INCOME	(11,000,000)		(11,000,000)		(22,000,000)		(21,000,000)
OTHER INCOME (EXPENSE):
Miscellaneous income, including net income from equity investees	(120,000,000)		(148,000,000)		(350,000,000)		(311,000,000)
Interest expense	16,000,000		16,000,000		32,000,000		32,000,000
Total other expense	(104,000,000)		(132,000,000)		(318,000,000)		(279,000,000)
INCOME (LOSS) BEFORE INCOME TAXES	(115,000,000)		(143,000,000)		(340,000,000)		(300,000,000)
INCOME TAXES	3,000,000		3,000,000		5,000,000		5,000,000
NET INCOME	(118,000,000)		(146,000,000)		(345,000,000)		(305,000,000)
Affiliates | Eliminations
EXPENSES:
Purchased power	(911,000,000)		(901,000,000)		(2,098,000,000)		(1,874,000,000)
FES
Consolidating Statements of Income
Revenues	1,292,000,000		1,326,000,000		2,684,000,000		2,714,000,000
EXPENSES:
Fuel	316,000,000		343,000,000		659,000,000		671,000,000
Other operating expenses	429,000,000		304,000,000		910,000,000		608,000,000
Provision for depreciation	68,000,000		63,000,000		136,000,000		126,000,000
General taxes	30,000,000		22,000,000		60,000,000		49,000,000
Impairment of long-lived assets	7,000,000				20,000,000		2,000,000
Total expenses	1,244,000,000		1,111,000,000		2,545,000,000		2,346,000,000
OPERATING INCOME	48,000,000		215,000,000		139,000,000		368,000,000
OTHER INCOME (EXPENSE):
Investment income	16,000,000		13,000,000		22,000,000		14,000,000
Miscellaneous income, including net income from equity investees	4,000,000		4,000,000		8,000,000		7,000,000
Interest expense	(52,000,000)		(51,000,000)		(105,000,000)		(101,000,000)
Capitalized interest	10,000,000		24,000,000		20,000,000		44,000,000
Total other expense	(24,000,000)		(12,000,000)		(58,000,000)		(41,000,000)
INCOME (LOSS) BEFORE INCOME TAXES	24,000,000		203,000,000		81,000,000		327,000,000
INCOME TAXES	4,000,000		69,000,000		25,000,000		113,000,000
NET INCOME	20,000,000		134,000,000		56,000,000		214,000,000
FES | Affiliates
EXPENSES:
Purchased power	65,000,000		69,000,000		134,000,000		130,000,000
OTHER INCOME (EXPENSE):
Interest expense	(2,000,000)		(2,000,000)		(3,000,000)		(5,000,000)
FES | Non-Affiliates
EXPENSES:
Purchased power	$ 329,000,000		$ 310,000,000		$ 626,000,000		$ 760,000,000

[1] *Includes excise tax collections of $116 million and $99 million in the three months ended June 30,2011 and 2010, respectively, and $235 million and $208 million in the six months ended June 30, 2011 and 2010, respectively.