PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Accumulated and Projected Benefit Obligations in Excess of Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation	$ 4,071	$ 3,762
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets	3,148	3,005
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Asses, Projected Benefit Obligation	4,097	3,786
Defied Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Fair Value of Plan Assets	3,148	3,005
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	$ 4,100	$ 3,800