EMPLOYEE BENEFIT PLANS - NET PENSION EXPENSE (Details) - Qualified Defined Benefit [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	$ 37	$ 41	$ 33
Interest cost	73	84	81
Expected return on assets	(108)	(122)	(117)
Amortization of prior service cost	(1)	(1)	(1)
Recognized actuarial loss	25	26	13
Settlement expense (special item)	0	14	0
Net pension expense	26	42	$ 9
Plan settlement	$ 0	$ 62