Merger (Details 5) (USD $) In Millions, except Per Share data	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Summary of consolidated results of operations
Revenue	$ 4,708	$ 5,072	$ 13,556	$ 14,158
Earnings available to FirstEnergy	$ 512	$ 300	$ 835	$ 944
Basic Earnings Per Share	$ 1.22	$ 0.72	$ 2.00	$ 2.26
Diluted Earnings Per Share	$ 1.22	$ 0.71	$ 1.99	$ 2.25

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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