PENSION AND OTHER POST-EMPLOYMENT BENEFITS - Schedule of Components of Net Periodic Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 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
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service costs	$ 35	34
Interest costs	99	109
Expected return on plan assets	(133)	(128)
Amortization of prior service costs (credits)	1	0
Net periodic benefit costs (credits)	2	15
Net periodic benefit costs (credits), net of amounts capitalized	(15)	(3)
OPEB
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service costs	1	1
Interest costs	5	5
Expected return on plan assets	(8)	(8)
Amortization of prior service costs (credits)	(1)	(2)
Net periodic benefit costs (credits)	(3)	(4)
Net periodic benefit costs (credits), net of amounts capitalized	$ (4)	$ (4)