PENSION AND OTHER POST-EMPLOYMENT BENEFITS - Schedule of Components of Net Periodic Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension and OPEB prior service costs amortized out of AOCI	$ 0	$ 1	$ 1	$ 2
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service costs	35	46	104	138
Interest costs	106	68	322	204
Expected return on plan assets	(151)	(164)	(421)	(492)
Amortization of prior service costs (credits)	1	1	2	2
Special termination benefits	13	0	18	0
Pension and OPEB mark-to-market adjustment			(59)	0
Net periodic benefit costs (credits)	4	(49)	(34)	(148)
Net periodic benefit costs (credits), net of amounts capitalized	(15)	(77)	(88)	(218)
OPEB
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service costs	1	1	2	3
Interest costs	5	3	16	8
Expected return on plan assets	(7)	(10)	(23)	(30)
Amortization of prior service costs (credits)	(3)	(3)	(7)	(8)
Special termination benefits	5	0	7	0
Pension and OPEB mark-to-market adjustment			0	0
Net periodic benefit costs (credits)	1	(9)	(5)	(27)
Net periodic benefit costs (credits), net of amounts capitalized	$ 1	$ (9)	$ (6)	$ (28)