Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income	$ 344	$ 463	$ 824	$ 856
OTHER COMPREHENSIVE INCOME (LOSS):
Pension and OPEB prior service costs	(2)	(3)	(6)	(10)
Amortized losses on derivative hedges	0	0	8	1
Other comprehensive income (loss)	(2)	(3)	2	(9)
Income taxes (benefits) on other comprehensive income (loss)	(1)	(1)	0	(3)
Other comprehensive income (loss), net of tax	(1)	(2)	2	(6)
COMPREHENSIVE INCOME	343	461	826	850
Comprehensive income attributable to noncontrolling interest	10	0	15	0
COMPREHENSIVE INCOME ATTRIBUTABLE TO FIRSTENERGY CORP.	$ 333	$ 461	$ 811	$ 850