INCOME TAXES - Provision for Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
-U.S. Federal	$ (272)	$ (169)	$ (1,253)
-U.S. State	(57)	(94)	(152)
-Non-U.S.	(161)	(284)	(178)
Current income tax expense	(490)	(547)	(1,583)
Deferred
-U.S. Federal	141	10	61
-U.S. State	39	(6)	(33)
-Non-U.S.	(16)	105	32
Deferred income tax expense	164	109	60
Provision for income taxes	$ (326)	$ (438)	$ (1,523)