EMPLOYEE BENEFIT PLANS - NET PENSION EXPENSE (Details) - Qualified Defined Benefit - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 7	$ 7
Interest cost	30	33
Expected return on assets	38	37
Recognized actuarial loss	(1)	(3)
Wages and Benefits
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Net pension expense	7	7
Nonoperating Income (Expense)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Net pension expense	$ (7)	$ (1)