Supplemental Guarantor Information (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Consolidated Statements of Cash Flows [Abstract]
Net cash provided from operating activities			$ 1,276	$ 2,229
New Financing-
Long-term debt			660	603
Short-term borrowings, net			1,604	0
Redemptions and Repayments-
Long-term debt			(870)	(1,581)
Short-term borrowings, net			0	(700)
Other			(42)	(73)
Net cash provided from (used for) financing activities			662	(2,402)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions	(775)	(500)	(1,686)	(1,464)
Nuclear fuel			(207)	(65)
Proceeds from asset sales			17	519
Sales of investment securities held in trusts			2,133	3,678
Purchases of investment securities held in trusts			(2,188)	(3,801)
Other			(40)	(6)
Net cash used for investing activities			(1,990)	(555)
Net change in cash and cash equivalents			(52)	(728)
Cash and cash equivalents at beginning of period			202	1,019
Cash and cash equivalents at end of period	150	291	150	291
FES Corp
Consolidated Statements of Cash Flows [Abstract]
Net cash provided from operating activities			(971)	(367)
New Financing-
Long-term debt			0	0
Short-term borrowings, net			982	750
Redemptions and Repayments-
Long-term debt			0	(136)
Short-term borrowings, net			0	0
Other			(1)	(8)
Net cash provided from (used for) financing activities			981	606
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			(10)	(8)
Nuclear fuel			0	0
Proceeds from asset sales			0	9
Sales of investment securities held in trusts			0	0
Purchases of investment securities held in trusts			0	0
Loans to affiliated companies, net			1	(228)
Other			(1)	(12)
Net cash used for investing activities			(10)	(239)
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0
Cash and cash equivalents at end of period	0	0	0	0
FGCO
Consolidated Statements of Cash Flows [Abstract]
Net cash provided from operating activities			683	539
New Financing-
Long-term debt			317	140
Short-term borrowings, net			49	59
Redemptions and Repayments-
Long-term debt			(169)	(351)
Short-term borrowings, net			0	0
Other			(6)	(1)
Net cash provided from (used for) financing activities			191	(153)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			(175)	(143)
Nuclear fuel			0	0
Proceeds from asset sales			17	510
Sales of investment securities held in trusts			0	0
Purchases of investment securities held in trusts			0	0
Loans to affiliated companies, net			(715)	(732)
Other			(5)	(24)
Net cash used for investing activities			(878)	(389)
Net change in cash and cash equivalents			(4)	(3)
Cash and cash equivalents at beginning of period			7	9
Cash and cash equivalents at end of period	3	6	3	6
Nuclear Generation Corp
Consolidated Statements of Cash Flows [Abstract]
Net cash provided from operating activities			799	374
New Financing-
Long-term debt			243	107
Short-term borrowings, net			0	25
Redemptions and Repayments-
Long-term debt			(87)	(313)
Short-term borrowings, net			(32)	0
Other			(2)	(2)
Net cash provided from (used for) financing activities			122	(183)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			(350)	(257)
Nuclear fuel			(207)	(65)
Proceeds from asset sales			0	0
Sales of investment securities held in trusts			1,167	1,613
Purchases of investment securities held in trusts			(1,194)	(1,654)
Loans to affiliated companies, net			(337)	172
Other			0	0
Net cash used for investing activities			(921)	(191)
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0
Cash and cash equivalents at end of period	0	0	0	0
Eliminations
Consolidated Statements of Cash Flows [Abstract]
Net cash provided from operating activities			(10)	(9)
New Financing-
Long-term debt			0	0
Short-term borrowings, net			(1,028)	(834)
Redemptions and Repayments-
Long-term debt			10	9
Short-term borrowings, net			32	(12)
Other				1
Net cash provided from (used for) financing activities			(986)	(836)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			0	0
Nuclear fuel			0	0
Proceeds from asset sales			0	0
Sales of investment securities held in trusts			0	0
Purchases of investment securities held in trusts			0	0
Loans to affiliated companies, net			996	845
Other			0	0
Net cash used for investing activities			996	845
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0
Cash and cash equivalents at end of period	0	0	0	0
FES
Consolidated Statements of Cash Flows [Abstract]
Net cash provided from operating activities			501	537
New Financing-
Long-term debt			560	247
Short-term borrowings, net			3	0
Redemptions and Repayments-
Long-term debt			(246)	(791)
Short-term borrowings, net			0	(12)
Other			(9)	(10)
Net cash provided from (used for) financing activities			308	(566)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			(535)	(408)
Nuclear fuel			(207)	(65)
Proceeds from asset sales			17	519
Sales of investment securities held in trusts			1,167	1,613
Purchases of investment securities held in trusts			(1,194)	(1,654)
Loans to affiliated companies, net			(55)	57
Other			(6)	(36)
Net cash used for investing activities			(813)	26
Net change in cash and cash equivalents			(4)	(3)
Cash and cash equivalents at beginning of period			7	9
Cash and cash equivalents at end of period	$ 3	$ 6	$ 3	$ 6