PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Revenue, Percentage from Products and Service Transferred to Customers	99.00%	99.00%
Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 99	$ 112
Interest cost	192	241
Expected return on plan assets	(414)	(417)
Amortization of prior service credit	(5)	(6)
Amortization of net (gain) loss	192	132
Net periodic benefit cost - including discontinued operations	64	62
Net periodic benefit cost	64	41
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	290
Defined Benefit Plan, Plan Assets, Contributions by Employer	63
Pension Plan [Member] | Discontinued Operations [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Net periodic benefit cost	0	21
Other Postretirement Benefits [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	2	2
Interest cost	9	14
Amortization of net (gain) loss	(2)	(6)
Net periodic benefit cost - including discontinued operations	$ 9	$ 10