PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Pension Plans [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 9	$ 10	$ 27	$ 30
Interest cost	36	32	108	96
Expected return on plan assets	(52)	(55)	(158)	(164)
Amortization of net (gain) loss	20	24	62	71
Net periodic benefit cost	13	11	39	33
Other Postretirement Benefits [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Interest cost	2	2	6	5
Amortization of net (gain) loss	(2)	(3)	(6)	(7)
Net periodic benefit cost	$ 0	$ (1)	$ 0	$ (2)