Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
NET INCOME	$ 869,000	$ 718,000	$ 856,000
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and other postretirement benefits	(90,000)	(220,000)	275,000
Unrealized gain (loss) on derivative hedges	23,000	36,000	51,000
Change in unrealized gain on available-for-sale securities	19,000	8,000	(74,000)
Other comprehensive income (loss)	(48,000)	(176,000)	252,000
Income taxes (benefits) on other comprehensive income (loss)	(49,000)	(74,000)	128,000
Other comprehensive income (loss), net of tax	1,000	(102,000)	124,000
COMPREHENSIVE INCOME (LOSS)	870,000	616,000	980,000
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO NONCONTROLLING INTEREST	(16,000)	(24,000)	(16,000)
COMPREHENSIVE INCOME (LOSS) AVAILABLE TO FIRSTENERGY CORP.	886,000	640,000	996,000
FES
NET INCOME	(59,000)	231,000	498,000
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and other postretirement benefits	(12,000)	(30,000)	68,000
Unrealized gain (loss) on derivative hedges	13,000	8,000	(49,000)
Change in unrealized gain on available-for-sale securities	15,000	23,000	18,000
Other comprehensive income (loss)	16,000	1,000	37,000
Income taxes (benefits) on other comprehensive income (loss)	2,000	4,000	14,000
Other comprehensive income (loss), net of tax	14,000	(3,000)	23,000
COMPREHENSIVE INCOME (LOSS)	(45,000)	228,000	521,000
OE
NET INCOME	128,000	155,000	119,000
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and other postretirement benefits	(43,000)	(31,000)	53,000
Unrealized gain (loss) on derivative hedges	0	0	(9,000)
Other comprehensive income (loss)	(43,000)	(31,000)	44,000
Income taxes (benefits) on other comprehensive income (loss)	(15,000)	(9,000)	19,000
Other comprehensive income (loss), net of tax	(28,000)	(22,000)	25,000
COMPREHENSIVE INCOME (LOSS)	100,000	133,000	144,000
CEI
NET INCOME	71,863	77,555	(28,757)
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and other postretirement benefits	(13,689)	(40,442)	46,188
Income taxes (benefits) on other comprehensive income (loss)	(6,842)	(14,732)	19,297
Other comprehensive income (loss), net of tax	(6,847)	(25,710)	26,891
COMPREHENSIVE INCOME (LOSS)	65,016	51,845	(1,866)
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO NONCONTROLLING INTEREST	1,293	1,517	1,714
COMPREHENSIVE INCOME (LOSS) AVAILABLE TO FIRSTENERGY CORP.	63,723	50,328	(3,580)
TE
NET INCOME	34,727	36,248	18,402
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and other postretirement benefits	(5,810)	(6,950)	9,078
Change in unrealized gain on available-for-sale securities	4,506	131	(15,181)
Other comprehensive income (loss)	(1,304)	(6,819)	(6,103)
Income taxes (benefits) on other comprehensive income (loss)	(1,296)	(1,421)	(533)
Other comprehensive income (loss), net of tax	(8)	(5,398)	(5,570)
COMPREHENSIVE INCOME (LOSS)	34,719	30,850	12,832
COMPREHENSIVE INCOME (LOSS) ATTRIBUTABLE TO NONCONTROLLING INTEREST	7	4	21
COMPREHENSIVE INCOME (LOSS) AVAILABLE TO FIRSTENERGY CORP.	34,712	30,846	12,811
JCP&L
NET INCOME	144,000	183,000	158,000
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and other postretirement benefits	(27,000)	(17,000)	(18,000)
Other comprehensive income (loss)	(27,000)	(17,000)	(18,000)
Income taxes (benefits) on other comprehensive income (loss)	(15,000)	(10,000)	(4,000)
Other comprehensive income (loss), net of tax	(12,000)	(7,000)	(14,000)
COMPREHENSIVE INCOME (LOSS)	132,000	176,000	144,000
Met-Ed
NET INCOME	67,889	60,084	53,537
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and other postretirement benefits	(21,149)	(12,968)	567
Unrealized gain (loss) on derivative hedges	335	335	335
Other comprehensive income (loss)	(20,814)	(12,633)	902
Income taxes (benefits) on other comprehensive income (loss)	(10,918)	(7,552)	3,070
Other comprehensive income (loss), net of tax	(9,896)	(5,081)	(2,168)
COMPREHENSIVE INCOME (LOSS)	57,993	55,003	51,369
Penelec
NET INCOME	63,073	63,190	50,798
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and other postretirement benefits	(27,960)	(20,421)	(820)
Unrealized gain (loss) on derivative hedges	65	65	79
Change in unrealized gain on investments	0	0	(17)
Other comprehensive income (loss)	(27,895)	(20,356)	(758)
Income taxes (benefits) on other comprehensive income (loss)	(14,566)	(11,794)	4,831
Other comprehensive income (loss), net of tax	(13,329)	(8,562)	(5,589)
COMPREHENSIVE INCOME (LOSS)	$ 49,744	$ 54,628	$ 45,209