EMPLOYEE BENEFIT PLANS - NET PENSION EXPENSE (Details) - Qualified Defined Benefit [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 42	$ 48	$ 39
Interest cost	89	79	74
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	95	107	106
Amortization of prior service cost	(1)	(1)	(1)
Defined Benefit Plan, Amortization of Gain (Loss)	(37)	(33)	(26)
Net pension expense	$ 72	$ 52	$ 32