PENSION AND OTHER POSTRETIREMENT BENEFIT PROGRAMS - Net Periodic Benefit Cost Relating to Pension and Other Postemployment Employee Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Pension benefits
Net periodic benefit cost
Service cost	$ 3	$ 4	$ 9	$ 13
Interest cost	34	33	102	123
Expected return on plan assets	(44)	(43)	(132)	(160)
Amortization of net losses and prior service costs	1	4	3	11
Net periodic pension cost (income)	(6)	(2)	(18)	(13)
OPEB
Net periodic benefit cost
Interest cost	2	2	6	6
Amortization of net losses and prior service costs	(4)	(5)	(12)	(14)
Net periodic pension cost (income)	$ (2)	$ (3)	$ (6)	$ (8)