DISCONTINUED OPERATIONS - Summarized Results of Discontinued Operations (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense (benefit)			$ (48)	$ (59)
Income from discontinued operations	[1]	$ 0	44	76
FES and FENOC | Discontinued Operations, Disposed of by Means Other than Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenues		0	0	7
Fuel		0	0	(6)
Other operating expenses		0	0	(6)
Pleasants economic interest		0	0	5
Other expense, net		0	(4)	0
Loss from discontinued operations, before tax		0	(4)	0
Income tax expense (benefit)		0	(1)	0
Loss from discontinued operations, net of tax		0	(3)	0
Settlement consideration and services credit		0	0	(1)
Accelerated net pension and OPEB prior service credits		0	0	18
Gain on disposal of FES and FENOC, before tax		0	0	17
Income tax benefits, including worthless stock deduction		0	(47)	(59)
Gain on disposal of FES and FENOC, net of tax		0	47	76
Income from discontinued operations		$ 0	$ 44	$ 76

[1] Net of income tax benefit of $48 million and $59 million in 2021 and 2020, respectively.