PENSION AND OTHER POST-EMPLOYMENT BENEFITS (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2023
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension and OPEB prior service costs amortized out of AOCI	$ 1	$ 1
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service costs	34	46
Interest costs	109	68
Expected return on plan assets	(128)	(164)
Amortization of prior service costs (credits)	0	1
Net periodic benefit costs (credits)	15	(49)
Net periodic benefit credits, net of amounts capitalized	(3)	(69)
Expected future contributions in 2025	250
Pension | Forecast
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated return			8.00%
OPEB
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service costs	1	1
Interest costs	5	3
Expected return on plan assets	(8)	(10)
Amortization of prior service costs (credits)	(2)	(3)
Net periodic benefit costs (credits)	(4)	(9)
Net periodic benefit credits, net of amounts capitalized	$ (4)	$ (9)