TAXES - Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Currently payable (receivable)-
Federal	$ 0	$ 2	$ (14)
State	11	21	21
Currently payable (receivable) Total	11	23	7
Deferred, net-
Federal	946	174	171
State	47	127	(38)
Deferred Tax Total	993	301	133
Investment tax credit amortization	(4)	(4)	(14)
Total income taxes	$ 1,000	320	126
Federal
Deferred, net-
Income tax expense (benefit), continuing operations, discontinued operations		2
Discontinued Operations, Disposed of by Means Other than Sale \| FES and FENOC \| Federal
Deferred, net-
Federal		$ 46	66
Discontinued Operations, Disposed of by Means Other than Sale \| FES and FENOC \| State and Local
Deferred, net-
Federal			$ 1

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