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Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

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Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Taxes (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
Taxes (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Currently payable (receivable)-
Federal									$ (16)	$ (16)	$ 14
State									24	17	20
Currently payable (receivable) Total									8	1	34
Deferred, net-
Federal									150	252	1,647
State									60	243	40
Deferred Tax Total									210	495	1,687
Investment tax credit amortization									(5)	(6)	(6)
Total income taxes	$ (68)	$ 107	$ 81	$ 93	$ 35	$ 121	$ 101	$ 233	213	490	1,715
Discontinued Operations, Disposed of by Means Other than Sale \| FES and FENOC
Currently payable (receivable)-
State										1	22
Discontinued Operations, Disposed of by Means Other than Sale \| FES and FENOC \| Federal
Deferred, net-
Federal									(9)	(1,300)	(771)
Discontinued Operations, Disposed of by Means Other than Sale \| FES and FENOC \| State and Local
Deferred, net-
Federal									$ 4	$ 12	$ (69)