Consolidated Balance Sheets (FirstEnergy Corp.) (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Common stockholders' equity-
Common stock, par value (in dollars per share)	$ 0.1	$ 0.1
Common stock, shares authorized	490,000,000us-gaap_CommonStockSharesAuthorized	490,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares outstanding	421,102,570us-gaap_CommonStockSharesOutstanding	418,628,559us-gaap_CommonStockSharesOutstanding
Customer [Member]
Receivables-
Allowance for uncollectible accounts (in dollars)	$ 59	$ 52
Other [Member]
Receivables-
Allowance for uncollectible accounts (in dollars)	$ 5	$ 3

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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