Taxes (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Changes in unrecognized tax benefits
Beginning balance		$ 117	$ 45	$ 191
Increase for tax positions related to the current year		2		10
Current year decreases		(7)		(78)
Increase due to merger with AE			97
Increase for tax positions related to prior years		6	10	2
Decrease for tax positions related to prior years		(37)	(35)	(81)
Decrease for settlement	(34)	(38)		(77)
Ending balance	43	43	117	45
FES
Changes in unrecognized tax benefits
Beginning balance		45	41	41
Increase for tax positions related to the current year		0		6
Current year decreases		0
Increase due to merger with AE			0
Increase for tax positions related to prior years		6	8	0
Decrease for tax positions related to prior years		(13)	(4)	(4)
Decrease for settlement		(35)		(2)
Ending balance	3	3	45	41
OE
Changes in unrecognized tax benefits
Beginning balance		0	2	77
Increase for tax positions related to the current year		0		2
Current year decreases		0
Increase due to merger with AE			0
Increase for tax positions related to prior years		0	0	0
Decrease for tax positions related to prior years		0	(2)	(19)
Decrease for settlement		0		(58)
Ending balance	0	0	0	2
JCP&L
Changes in unrecognized tax benefits
Beginning balance		0	0	14
Increase for tax positions related to the current year		0		0
Current year decreases		0
Increase due to merger with AE			0
Increase for tax positions related to prior years		0	0	0
Decrease for tax positions related to prior years		0	0	(21)
Decrease for settlement		0		7
Ending balance	$ 0	$ 0	$ 0	$ 0

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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