EMPLOYEE BENEFIT PLANS - NET PENSION EXPENSE (Details) - Qualified Defined Benefit [Member] - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	$ 10	$ 9	$ 20	$ 18
Interest cost	18	19	36	37
Expected return on assets	(26)	(27)	(53)	(54)
Recognized actuarial loss	6	6	13	12
Net pension expense	$ 8	$ 7	$ 16	$ 13