TAXES - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended			12 Months Ended
	Apr. 30, 2023	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2024	Mar. 31, 2023	Aug. 16, 2022	May 31, 2022
Provision for Income Tax [Line Items]
Valuation allowances		$ 37			$ (146)	$ (47)	$ 17
Operating loss carryforwards, not subject to expiration, net of tax		1,200			1,200					$ 1,000
Income taxes paid	$ 49
Operating loss carryforwards, subject to expiration		8,100			8,100
Nondeductible DPA monetary penalty		58		$ 752
Income taxes (benefits)			$ 65		267	1,000	$ 320
Deferred tax assets		4			4				$ 9
Deferred tax assets, expected to be refunded to customers		4			4
Operating loss carryforwards, subject to expiration, net of tax		1,700			1,700
Operating loss carryforwards, not subject to expiration		5,900			5,900
Tax credit carryforwards not subject to expiration		57			57
Tax credit carryforwards subject to expiration		12			12
Interest expense reversed due to settlement		9			9
Interest Expense Carryforward
Provision for Income Tax [Line Items]
Valuation allowances						$ 38
State and Local Jurisdiction [Member]
Provision for Income Tax [Line Items]
Operating loss carryforwards, not subject to expiration, net of tax		436			436
Operating loss carryforwards, not subject to expiration		13,500			13,500
Pre-tax net operating loss carryforwards expected to utilized		6,100			6,100
Operating loss carryforwards expected to utilized, net of tax		$ 233			$ 233
Brookfield II | FET
Provision for Income Tax [Line Items]
Sale of ownership interest by parent		19.90%			19.90%						19.90%
Brookfield II | Forecast | FET
Provision for Income Tax [Line Items]
Additional sale of ownership interest by parent								30.00%
Sale of ownership interest by parent								49.90%
Operating loss carryforwards, subject to expiration								$ 7,500