PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 99	$ 95	$ 198	$ 207
Interest cost	191	227	383	468
Expected return on plan assets	(412)	(421)	(826)	(838)
Amortization of prior service credit	(5)	(5)	(10)	(11)
Amortization of net (gain) loss	192	147	384	279
Curtailment/special termination benefits 1	0	(27)	0	(27)
Net periodic benefit cost - including discontinued operations	65	16	129	78
Net periodic benefit cost	65	16	129	57
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	290		290
Defined Benefit Plan, Plan Assets, Contributions by Employer			112
Pension Plan [Member] | Discontinued Operations [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Net periodic benefit cost	0	0	0	21
Other Postretirement Benefits [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	2	2	4	4
Interest cost	10	12	19	26
Amortization of net (gain) loss	(3)	(5)	(5)	(11)
Curtailment/special termination benefits 1	0	(3)	0	(3)
Net periodic benefit cost	$ 9	$ 6	$ 18	$ 16