TAXES - Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Currently payable (receivable)-
Federal	$ 2	$ (14)	$ (16)
State	21	21	24
Currently payable (receivable) Total	23	7	8
Deferred, net-
Federal	174	171	150
State	127	(38)	60
Deferred Tax Total	301	133	210
Investment tax credit amortization	(4)	(14)	(5)
Total income taxes	320	126	213
Federal
Deferred, net-
Income tax expense (benefit), continuing operations, discontinued operations	2	6
Discontinued Operations, Disposed of by Means Other than Sale \| FES and FENOC \| Federal
Deferred, net-
Federal	$ 46	66	9
Discontinued Operations, Disposed of by Means Other than Sale \| FES and FENOC \| State and Local
Deferred, net-
Federal		$ 1	$ 4

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