SEGMENT INFORMATION - Segment Financial Information (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Segment Financial Information
Total revenues	[1]	$ 3,729	$ 3,487	$ 10,296	$ 9,724
Depreciation		400	366	1,178	1,088
Amortization (deferral) of regulatory assets, net		(33)	(140)	(205)	(253)
Equity method investment earnings		21	43	64	134
Interest expense		276	289	866	828
Income taxes (benefits)		94	29	294	193
Earnings (losses) attributable to FE from continuing operations		419	421	717	948
Cash Flows from Investing Activities:
Capital investments		1,004	848	2,736	2,266
Assets		50,756		50,756		$ 48,767
Goodwill		5,618		5,618		5,618
Distribution
Cash Flows from Investing Activities:
Goodwill		3,222		3,222
External revenues
Segment Financial Information
Total revenues		3,729	3,487	10,296	9,724
Internal revenues
Segment Financial Information
Total revenues		0	0	0	0
Operating Segments
Segment Financial Information
Total revenues		3,744	3,500	10,338	9,764
Depreciation		379	348	1,121	1,033
Amortization (deferral) of regulatory assets, net		(33)	(140)	(205)	(253)
Equity method investment earnings		0	0	0	0
Interest expense		238	229	730	656
Income taxes (benefits)		110	91	344	267
Earnings (losses) attributable to FE from continuing operations		462	420	1,050	1,097
Cash Flows from Investing Activities:
Capital investments		970	834	2,678	2,233
Assets		51,240		51,240		48,843
Goodwill		5,618		5,618		5,618
Operating Segments | Distribution
Segment Financial Information
Total revenues		1,817	1,795	5,232	5,239
Depreciation		163	155	486	464
Amortization (deferral) of regulatory assets, net		(55)	(124)	(152)	(174)
Equity method investment earnings		0	0	0	0
Interest expense		106	100	331	290
Income taxes (benefits)		34	46	96	122
Earnings (losses) attributable to FE from continuing operations		193	175	426	506
Cash Flows from Investing Activities:
Capital investments		289	233	758	662
Assets		19,795		19,795		19,235
Goodwill		3,222		3,222		3,222
Operating Segments | Integrated
Segment Financial Information
Total revenues		1,452	1,266	3,725	3,250
Depreciation		132	116	386	343
Amortization (deferral) of regulatory assets, net		20	(17)	(58)	(85)
Equity method investment earnings		0	0	0	0
Interest expense		62	67	198	187
Income taxes (benefits)		36	12	107	43
Earnings (losses) attributable to FE from continuing operations		197	145	387	290
Cash Flows from Investing Activities:
Capital investments		382	312	1,045	824
Assets		18,082		18,082		17,466
Goodwill		1,953		1,953		1,953
Operating Segments | Stand-Alone Transmission
Segment Financial Information
Total revenues		475	439	1,381	1,275
Depreciation		84	77	249	226
Amortization (deferral) of regulatory assets, net		2	1	5	6
Equity method investment earnings		0	0	0	0
Interest expense		70	62	201	179
Income taxes (benefits)		40	33	141	102
Earnings (losses) attributable to FE from continuing operations		72	100	237	301
Cash Flows from Investing Activities:
Capital investments		299	289	875	747
Assets		13,363		13,363		12,142
Goodwill		443		443		443
Operating Segments | External revenues
Segment Financial Information
Total revenues		3,727	3,486	10,290	9,718
Operating Segments | External revenues | Distribution
Segment Financial Information
Total revenues		1,806	1,786	5,202	5,209
Operating Segments | External revenues | Integrated
Segment Financial Information
Total revenues		1,451	1,266	3,721	3,247
Operating Segments | External revenues | Stand-Alone Transmission
Segment Financial Information
Total revenues		470	434	1,367	1,262
Operating Segments | Internal revenues
Segment Financial Information
Total revenues		17	14	48	46
Operating Segments | Internal revenues | Distribution
Segment Financial Information
Total revenues		11	9	30	30
Operating Segments | Internal revenues | Integrated
Segment Financial Information
Total revenues		1	0	4	3
Operating Segments | Internal revenues | Stand-Alone Transmission
Segment Financial Information
Total revenues		5	5	14	13
Corporate/Other
Segment Financial Information
Total revenues		2	1	6	6
Depreciation		21	18	57	55
Amortization (deferral) of regulatory assets, net		0	0	0	0
Equity method investment earnings		21	43	64	134
Interest expense		80	87	281	248
Income taxes (benefits)		(16)	(62)	(50)	(74)
Earnings (losses) attributable to FE from continuing operations		(43)	1	(333)	(149)
Cash Flows from Investing Activities:
Capital investments		34	14	58	33
Assets		1,879		1,879		2,372
Goodwill		0		0		0
Corporate/Other | External revenues
Segment Financial Information
Total revenues		2	1	6	6
Corporate/Other | Internal revenues
Segment Financial Information
Total revenues		0	0	0	0
Reconciling Adjustments
Segment Financial Information
Total revenues		(17)	(14)	(48)	(46)
Depreciation		0	0	0	0
Amortization (deferral) of regulatory assets, net		0	0	0	0
Equity method investment earnings		0	0	0	0
Interest expense		(42)	(27)	(145)	(76)
Income taxes (benefits)		0	0	0	0
Earnings (losses) attributable to FE from continuing operations		0	0	0	0
Cash Flows from Investing Activities:
Capital investments		0	0	0	0
Assets		(2,363)		(2,363)		(2,448)
Goodwill		0		0		$ 0
Reconciling Adjustments | External revenues
Segment Financial Information
Total revenues		0	0	0	0
Reconciling Adjustments | Internal revenues
Segment Financial Information
Total revenues		$ (17)	$ (14)	$ (48)	$ (46)

[1] Includes excise and gross receipts tax collections of $116 million and $114 million during the three months ended September 30, 2024 and 2023, respectively, and $329 million and $315 million during the nine months ended September 30, 2024 and 2023, respectively.