Supplemental Guarantor Information (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Consolidated Statements of Cash Flows [Abstract]
NET CASH PROVIDED FROM (USED FOR) OPERATING ACTIVITIES	$ (413)	$ 491
New Financing-
Long-term debt	0	217
Short-term borrowings, net	1,075	0
Redemptions and Repayments-
Long-term debt	(16)	(359)
Short-term borrowings, net	0	(214)
Other	(10)	(4)
Net cash provided from (used for) financing activities	819	(550)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions	(589)	(449)
Sales of investment securities held in trusts	251	969
Purchases of investment securities held in trusts	(266)	(993)
Other	(8)	(23)
Net cash provided from (used for) investing activities	(534)	141
Net change in cash and cash equivalents	(128)	82
Cash and cash equivalents at beginning of period	202	1,019
Cash and cash equivalents at end of period	74	1,101
FES Corp
Consolidated Statements of Cash Flows [Abstract]
NET CASH PROVIDED FROM (USED FOR) OPERATING ACTIVITIES	(419)	(215)
New Financing-
Long-term debt		0
Short-term borrowings, net	347	322
Redemptions and Repayments-
Long-term debt		(131)
Short-term borrowings, net	0
Other		(1)
Net cash provided from (used for) financing activities	347	190
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions	(2)	(3)
Sales of investment securities held in trusts	0	0
Purchases of investment securities held in trusts	0	0
Loans to affiliated companies, net	74	28
Customer acquisition costs		0
Other	0	0
Net cash provided from (used for) investing activities	72	25
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
FGCO
Consolidated Statements of Cash Flows [Abstract]
NET CASH PROVIDED FROM (USED FOR) OPERATING ACTIVITIES	66	267
New Financing-
Long-term debt		90
Short-term borrowings, net	0	28
Redemptions and Repayments-
Long-term debt		(141)
Short-term borrowings, net	(20)
Other	(2)	0
Net cash provided from (used for) financing activities	(22)	(23)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions	(18)	(40)
Sales of investment securities held in trusts	0	0
Purchases of investment securities held in trusts	0	0
Loans to affiliated companies, net	(23)	(200)
Customer acquisition costs		0
Other	(3)	(6)
Net cash provided from (used for) investing activities	(44)	(246)
Net change in cash and cash equivalents	0	(2)
Cash and cash equivalents at beginning of period	7	9
Cash and cash equivalents at end of period	7	7
Nuclear Generation Corp
Consolidated Statements of Cash Flows [Abstract]
NET CASH PROVIDED FROM (USED FOR) OPERATING ACTIVITIES	175	42
New Financing-
Long-term debt		60
Short-term borrowings, net	0	0
Redemptions and Repayments-
Long-term debt		(60)
Short-term borrowings, net	(32)
Other	(1)	0
Net cash provided from (used for) financing activities	(33)	0
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions	(161)	(116)
Sales of investment securities held in trusts	83	216
Purchases of investment securities held in trusts	(90)	(231)
Loans to affiliated companies, net	25	90
Customer acquisition costs		0
Other	1	(1)
Net cash provided from (used for) investing activities	(142)	(42)
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
Eliminations
Consolidated Statements of Cash Flows [Abstract]
NET CASH PROVIDED FROM (USED FOR) OPERATING ACTIVITIES	0	0
New Financing-
Long-term debt		0
Short-term borrowings, net	(347)	0
Redemptions and Repayments-
Long-term debt		0
Short-term borrowings, net	52
Other		0
Net cash provided from (used for) financing activities	(295)	0
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions	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	295	0
Customer acquisition costs		0
Other	0	0
Net cash provided from (used for) investing activities	295	0
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
FES
Consolidated Statements of Cash Flows [Abstract]
NET CASH PROVIDED FROM (USED FOR) OPERATING ACTIVITIES	(178)	94
New Financing-
Long-term debt	0	150
Short-term borrowings, net	0	350
Redemptions and Repayments-
Long-term debt	0	(332)
Short-term borrowings, net	0
Other	(3)	(1)
Net cash provided from (used for) financing activities	(3)	167
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions	(181)	(159)
Sales of investment securities held in trusts	83	216
Purchases of investment securities held in trusts	(90)	(231)
Loans to affiliated companies, net	371	(82)
Customer acquisition costs		0
Other	(2)	(7)
Net cash provided from (used for) investing activities	181	(263)
Net change in cash and cash equivalents	0	(2)
Cash and cash equivalents at beginning of period	7	9
Cash and cash equivalents at end of period	$ 7	$ 7