RETIREMENT AND POSTRETIREMENT BENEFIT PLANS - NARRATIVE (Details) $ in Millions			12 Months Ended
	Jun. 30, 2020 USD ($)	Aug. 08, 2019 USD ($)	Dec. 31, 2020 USD ($) employee	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Defined Benefit Plan Disclosure
Accrued liabilities for the supplemental retirement plan			$ 239	$ 261
Expenses under provisions of defined contribution and supplemental retirement plans			192	192	$ 152
Total benefit costs, including postretirement costs			$ 235	220	$ 182
United States
Defined Benefit Plan Disclosure
Number of employees accruing benefits under defined benefit plans | employee			400
Foreign
Defined Benefit Plan Disclosure
Number of employees accruing benefits under defined benefit plans | employee			300
Pension Benefits
Defined Benefit Plan Disclosure
Additions due to the Acquisition		$ 193	$ 0	2,136
Curtailment gain	$ 124		278	136
Offset to accumulated other comprehensive income	154
Decrease to benefit obligation	$ 278		$ 8	$ (13)