PROPERTY, PLANT AND EQUIPMENT - Operating Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Property, Plant and Equipment [Abstract]
Long-term (fixed)	$ 183	$ 219	$ 360	$ 445
Long-term (variable)	24	27	45	71
Short-term	54	43	123	90
Total Operating lease expense	$ 261	$ 289	$ 528	$ 606