Short-Term Borrowings and Bank Lines of Credit (Details) (USD $)	Jan. 31, 2014	Jan. 31, 2014 Subsequent Event	Dec. 31, 2013 FirstEnergy		Jan. 31, 2014 FirstEnergy Revolving Credit Facility		Jan. 31, 2014 FirstEnergy Revolving Credit Facility Subsequent Event		Jan. 31, 2014 FES / AE Supply Revolving Credit Facility	Jan. 31, 2014 FES / AE Supply Revolving Credit Facility Subsequent Event	Dec. 31, 2013 FET		Jan. 31, 2014 FET Revolving Credit Facility		Jan. 31, 2014 FET Revolving Credit Facility Subsequent Event
Short-term Debt [Line Items]
Maximum amount borrowed under revolving credit facility	$ 6,000,000,000		$ 2,500,000,000	[1]	$ 2,500,000,000	[2]			$ 2,500,000,000		$ 1,000,000,000	[1]	$ 1,000,000,000	[3]
Available Liquidity		2,713,000,000					224,000,000	[2]		2,489,000,000					0	[3]
Cash, Available Liquidity		48,000,000
Total Available Liquidity		$ 2,761,000,000

[1] (1)No limitations.

[2] (1)FE and the Utilities

[3] (2)Includes FET, ATSI and TrAIL as subsidiary borrowers