INCOME TAXES - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Income before income taxes (continuing operations)	$ 470	$ 449	$ 1,198	$ 1,061
Federal income tax expense at statutory rate (21%)	99	94	252	223
Increases (reductions) in tax expense resulting from:
State income taxes, net of federal tax benefit	25	25	49	68
AFUDC equity and other flow-through	(15)	(8)	(25)	(23)
Excess deferred tax amortization due to the Tax Act	2	(15)	(30)	(46)
Federal tax credits claimed	(2)	(3)	(2)	(3)
Valuation allowances	(122)	(8)	(113)	26
Remeasurement of state deferred taxes due to law changes	0	4	0	(22)
Uncertain tax positions	50	2	50	2
Other, net	(8)	14	12	12
Total income taxes (continuing operations)	$ 29	$ 105	$ 193	$ 237
Effective income tax rate (continuing operations)	6.00%	23.40%	16.10%	22.30%