PENSION AND OTHER POSTRETIREMENT BENEFITS - Amounts Recognized in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	$ (1,448)	$ (1,585)
Net prior service cost	(1)	(1)
Net amount recognized in accumulated other comprehensive income (loss) before tax	(1,449)	(1,586)
Deferred income taxes	390	424
Net amount recognized in accumulated other comprehensive income (loss)	(1,059)	(1,162)
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net actuarial (loss) gain	147	150
Net prior service cost	0	0
Net amount recognized in accumulated other comprehensive income (loss) before tax	147	150
Deferred income taxes	(14)	(15)
Net amount recognized in accumulated other comprehensive income (loss)	$ 133	$ 135